Why do people litter a post with comments then block OP?

This has happened on more than one post of mine.

Someone will litter the thread with commentary. I’ll respond and then when I’m going through the thread later I won’t see their comments but the number of comments will remain the same.

What is the point of that?

Better yet what is the point of interacting with a post that you know doesn’t matter to you or that you don’t have actual commentary on.

It’s so annoying and detracts from actual conversations that could be had.

Bean soup all over again.