Same thing happened to me. I admit I'll rage post sometimes and sure I might deserve a subreddit ban here or there. But I've never done anything worthy of a site-wide ban. But the reddit admins act like dictators on a power trip. They LOVE to slap people with site-wide bans. For no good reason, and I don't understand it. The admins have turned the whole site toxic, and places like Lemmy are a direct response to their insane powertripping.
Right now it sucks. Reddit is still the most popular forum on the internet. I pray that someday it won't be.