A few dozen users, mostly bots or people posting in non-English with their accounts setup incorrectly to tag it as English.
Actual humans who I think are idiots or trolls, I’m more likely to just tag them instead of blocking them. I see the tag and it reminds me not to waste my time answering them, but I can still see other people making interesting responses. Like there’s a chronically depressed dude who posts frequently, asks for advice, then insults anyone who replies. He caught me twice, then I tagged him and I no longer take his bait. But some other people who reply to him have genuinely good comments and I can still see them.
Boost also has a tagging feature. Their Lemmy app may be even better than their old reddit app.