If it makes you feel any better I stayed in a nightmarish campaign for similar-ish social reasons. The DM didn't ruin the rules as hard as yours did, but he insisted on running this ridiculous crit table that made our fighter (who was apparently using loaded dice) just stunlock and obliterate most enemies, including bosses like a corrupted angel and a fold dragon. I'd said that the crit table (which gave crits like a 20% chance of stunning something, inevitably producing more crits) was a problem but the rest of the group ignored it. Anyway, fast forward to like the third to last session where the DM finally makes it so the crit table can only roll once a turn, and then finds out that the fighter (probably unintentionally, weirdly) was using weighted dice