It's been a while since you posted, but I thought I would comment anyway.
My theory behind reactions like these is that FATE is quite different from the "standard, rules heavy" rpg experience people are used to. People who have never played a light system go into fate and find the flexibility offputting. I found it quite hard to grok myself, even though I prefer these types of systems myself. Maybe an analogy of my own.
Terry has spent their entire life shopping at Ikea for furniture - to the point that they are utterly dependent on the choices they offer. If Ikea sells something, they know about it, and if they don't, they avoid it. Ikea doesn't sell lumber, only finished furniture.
Then Terry enters your store, treating it like an Ikea. He asks to see the showroom, and is told there is none. He look through the hardware section, and the lumber yard and tries to give your store a chance, but he is overwhelmed by the choices, he's never had to think about these kinds of things before. He asks the clerk, "I want a Kallax!". The clerk says, "We don't have a Kallax, but we can construct something similar. But before reaching for cube storage, maybe you should consider finding a more specialized storage solution, like a bookshelf, perhaps? Here are some examples!" Upon seeing some hand-crafted bookshelves and drawers, terry finds himself excersizing parts of his brain that have never been used. "That's a strange feeling, shouldn't the clerk be doing all the work here? If I'm paying, I shouldn't have to make these decisions!" Terry asks for a Kallax once again, and the team tries to make one - but the result ends up being very different from what Terry is used to - solid wood rather than particle board, imperfections due to the hand-crafted nature, and it's a pain to transport something already assembled. If you squint, it's a Kallax, but it lacks the essence that Terry was expecting. Terry leaves and is dissapointed with the store.
Bringing it back to FATE and maybe the magic system, and substituting me instead of Terry. I (unlike Terry) am deeply unhappy with 5e's magic and combat system. I find it much too complex and promoting gameplay I dislike. It won't fit into the setting I want to run, which has ridiculously complicated Magic "rules". So I turn to FATE, and I'm met with countless choices. Magic system as an aspect, stunts, skills? What's an extra, isn't that just homebrew? I don't even know what an aspect is! If there's no spell slots, how can I balance power? What's stopping a player from casting "Wish" all the time?
It wasn't until I played over 5 games of FATE, experimenting with different ways of playing, before I began to grok it. Suddenly all these words click! A magic skill could be useful in a low magic word, but you have to be a bit careful to make sure one stat dosen't get used for everything. Stunts are good for specific "powers", maybe mapping to superheros. And if you want something even lighter, just make it an aspect, and make sure to be aggressive about enforcing narrative limits. If you have a very clear mechanical vision, maybe you can make something crunchy using extras and some light tracking.
But imagine me being someone already happy with 5e's magic system - I would have been constantly trying to fit aspects, stunts, and extras to match 5e, setting up spell levels, slots, preparation, etc. And once I'm all done, I'll still be unhappy, because I'll constantly be comparing the giant pile of homebrew I made with 5e, and be dissapointed! An example for me, I play a star wars game (FFG), that I was thinking about moving into FATE. After going through this homebrew: https://fate-accelerated-star-wars-the-infinite-empire.obsidianportal.com/wiki_pages/the-force I realized this was a futile task - why bother building this complicated system when there are systems built for the setting already? Just fix the problems from a better known "starting point".
Anyway, as someone who's been in both positions, hopefully that can explain both sides of this.
It's been a while since you posted, but I thought I would comment anyway.
My theory behind reactions like these is that FATE is quite different from the "standard, rules heavy" rpg experience people are used to. People who have never played a light system go into fate and find the flexibility offputting. I found it quite hard to grok myself, even though I prefer these types of systems myself. Maybe an analogy of my own.
Terry has spent their entire life shopping at Ikea for furniture - to the point that they are utterly dependent on the choices they offer. If Ikea sells something, they know about it, and if they don't, they avoid it. Ikea doesn't sell lumber, only finished furniture. Then Terry enters your store, treating it like an Ikea. He asks to see the showroom, and is told there is none. He look through the hardware section, and the lumber yard and tries to give your store a chance, but he is overwhelmed by the choices, he's never had to think about these kinds of things before. He asks the clerk, "I want a Kallax!". The clerk says, "We don't have a Kallax, but we can construct something similar. But before reaching for cube storage, maybe you should consider finding a more specialized storage solution, like a bookshelf, perhaps? Here are some examples!" Upon seeing some hand-crafted bookshelves and drawers, terry finds himself excersizing parts of his brain that have never been used. "That's a strange feeling, shouldn't the clerk be doing all the work here? If I'm paying, I shouldn't have to make these decisions!" Terry asks for a Kallax once again, and the team tries to make one - but the result ends up being very different from what Terry is used to - solid wood rather than particle board, imperfections due to the hand-crafted nature, and it's a pain to transport something already assembled. If you squint, it's a Kallax, but it lacks the essence that Terry was expecting. Terry leaves and is dissapointed with the store.
Bringing it back to FATE and maybe the magic system, and substituting me instead of Terry. I (unlike Terry) am deeply unhappy with 5e's magic and combat system. I find it much too complex and promoting gameplay I dislike. It won't fit into the setting I want to run, which has ridiculously complicated Magic "rules". So I turn to FATE, and I'm met with countless choices. Magic system as an aspect, stunts, skills? What's an extra, isn't that just homebrew? I don't even know what an aspect is! If there's no spell slots, how can I balance power? What's stopping a player from casting "Wish" all the time? It wasn't until I played over 5 games of FATE, experimenting with different ways of playing, before I began to grok it. Suddenly all these words click! A magic skill could be useful in a low magic word, but you have to be a bit careful to make sure one stat dosen't get used for everything. Stunts are good for specific "powers", maybe mapping to superheros. And if you want something even lighter, just make it an aspect, and make sure to be aggressive about enforcing narrative limits. If you have a very clear mechanical vision, maybe you can make something crunchy using extras and some light tracking. But imagine me being someone already happy with 5e's magic system - I would have been constantly trying to fit aspects, stunts, and extras to match 5e, setting up spell levels, slots, preparation, etc. And once I'm all done, I'll still be unhappy, because I'll constantly be comparing the giant pile of homebrew I made with 5e, and be dissapointed! An example for me, I play a star wars game (FFG), that I was thinking about moving into FATE. After going through this homebrew: https://fate-accelerated-star-wars-the-infinite-empire.obsidianportal.com/wiki_pages/the-force I realized this was a futile task - why bother building this complicated system when there are systems built for the setting already? Just fix the problems from a better known "starting point".
Anyway, as someone who's been in both positions, hopefully that can explain both sides of this.