If you have millions of people on a social network, and you go looking for toxic shit there, you will find it.

Well, on Mastodon, you might not because by default it doesn't have a useful text search feature. If you're on a server running a modified version, or something else with decent text search, you might. My self-hosted server was on a relay that briefly pulled in content from a famously toxic server. At first, I didn't see it because I didn't follow those accounts, but later, I added an improved search feature and tried searching for some terms of abuse. I did find a few absolutely vile posts.

Bluesky has had a working search from early on. Turning off some of the default moderation filters and searching for terms of abuse does, in fact find people using terms of abuse.