In general I've found Lemmy to be closer to the feel of old forums in interactions. Arguments and petty squabbles are still entirely possible, but it doesn't feel like every interaction is about to become one. It's what pushed me to stop using Reddit - everything seems to end up as a fight for the slightest reason. Whilst I'm plenty abrasive as a person, it felt like Reddit got worse over the last 5 - 10 years.
They might have a bigger userbase now than when I joined but it's not ended up being worth it, I feel.