Not sure what has changed but I'm being overrun with bots from various Mastodon sites, it started with Mastodon social but has spread to Mastodon.art and other Mastodon sites.

The bots almost always start with a series of three posts, the first of which starts with "Hi I'm" ... some bullshit description, and then a couple more posts by same with totally inane content. The bots often make eight or nine comments on their own posts in the complex absence of comments by anyone else.

I've been blocking them individually when I can but when a site just overruns me I am blocking the entire site. I hope the developers are aware and doing something to counter act. The site admins don't seem to be.