Correct, it is mobile only. Unfortunately, I think I must be misunderstanding what you’re saying about the OP stuff. This is my view, the way I think about it at least, these are all “OPs”, ones with a plus sign next to the leftward arrow have comments.

And then if I tap, I get the op with its comments underneath it.

Try Fedilab, I think it will be more intuitive for you, unless I’m misunderstanding your frustration.