You can argue that blocking is the wrong name for the feature. Ignore might be a far better word for the feature, because that is what it does.
And you do can ban users from commenting on your published projects. I commented on your project, so you can test that feature.
Since you can't interact with other users, other than publicly commenting, an ignore feature is all that is needed for the limited social media capabililty of itch.
Okay. Still, consider this: someone just followed you here on itch, and by their name and behavior towards you, you can clearly tell who it is - and that they came with ill intentions in mind. It might be a stalker that’s keeping tabs on every single site you’re on.
This can severely impact someone’s mental health, knowing that they’re actively stalked - but powerless to do anything about it. That’s why you need to have these moderation tools. Maybe not to the extent other sites offer it… but the “follower removal” thing is the least one can ask for.
