Here's some resources that I use often:

• mtggoldfish has meta decks and user submitted decks for almost all popular formats out there. They include a meta % to show how much a deck is played.
• for more competitive meta results I use mtgdecks.net, where you can filter on recent tournaments or MTGO leagues within the format you're interested in.
• lastly there's aetherhub, which I use less these days but is also a good source for meta deck finding.
• if you're looking for meta discussions and deck techs, you can still find them on reddit, e.g. the /r/spikes subreddit or the subreddit for the format of your choice, for Pioneer there's /r/PioneerMTG

Can't, they release new cards every few weeks. Plus competitive scene is dead and unsupported.

I played since unlimited competitively and stopped when they stopped supporting LSGs and tournament play.

Just draft if you want to keep one foot in.

What is the current land tax? That’s a good question as well.