Blocking keeps my feed nice. See people being assholes? Block them. See a post discussing something I don’t want to hear about? Block them. See a community I don’t want to hear about? Block them. The greatest thing about social media is the ability to never have to interact with someone again at no detriment to them. Blocking is good.
It’s a good tool and I encourage people to use it. Otherwise the asshole filter can start to take over. I’d honestly prefer someone to block me if I annoy them, rather than try to engage me in some snark-fest or pointless argument.
I also think it’s best just to block and move on if someone acts like a jerk. Don’t respond or tell them you are blocking them. Let them shout into the void.
One of the main things I look for is the person’s comment history. If they seldom post an original thought or comment and mostly reply just to be nasty and condescending towards other people, I will block them. They are basically using the people in forums as a bunch of paper targets to snipe at. Once you know to look for them, you can spot these type of commenters pretty quickly.
In highly controversial threads I will often spot new people to block that I did not even engage with.
I’ve only had two people say they would block me. In both cases it was me asking questions about their comment and them getting angry and not having or wanting to give an answer.
I only block when people get personal for no particular reason.