do they get a notification or like can they see that their opinion has been deleted
Most Helpful Guy
They figure it out after trying to post on any of your non-anonymous questions, or your any of your opinions, or tries to upvote/downvote one of your opinions.
Or if they try to upvote your answer as an anonymous question asker. Because that doesn't work either if they're blocked.0
Most Helpful Girl
They can only tell if they try to answer any of your non-anonymous questions or opinions or if they try to upvote one of your posts. That's the only way to know.
There is no such notification that can let you know when someone blocks you as far as I know.0