The problem is, that Itch cannot reliable say who is legit and who not. That's my educated guess.
I support this with the fact that the latest scam spammer I saw was an account created in 2024.
due to this community's settings
You forgot this part of the reasoning. An often wished for feature by developers is to have at least restricted comment sections.
And I guess the overall system setting of communities is currently something that puts a lot of comments on that moderator approval waiting list.
I am not even sure who moderates those. Because people that work for Itch are not usually called moderators. Maybe it is the developers themselves in some cases. Or there are "moderators" that just do not talk and are different from the blue community mods (like no time). I think no time would have noticed the workload of approving a ton of comments.