Doesn't make them good or necessary just because they're common. When I see bots, I tend to block them pretty fast regardless of contribution, and my experience has been pretty damn nice here in very large part because the bot users are (to my knowledge) mostly or entirely dormant.

Nobody wants to interact with a known bot, or post where that's the main contributor. The bot is never going to engage with them, and it somehow feels worse than posting into the void.