I don't know if there's some technical reason why the limit is there, but I would like to be able to write thoughts about a game on my profile that are longer than 2000 characters. Right after finishing a game, I like to jot down my thoughts about the whole thing, but that can easily become more than the limit. I am not sure what would be a good limit to set instead.

I don't remember any specific reason for the 2000 character limit. The only thing I can think of is thoughts are displayed in a small-ish area on the Profile page, so lengthier ones can suffer from readability issues. I can try bumping it up a bit and see if that helps.

I guess my use case might fall out of what is expected of the Thoughts feature. All I am wanting to do is have a place to write down rough reviews of what I play. I just noticed that community articles might be more targeted for that, although I am not really writing it for anyone but myself.

I believe there is a place to add notes to a game on the collection page. I've never used it but maybe that's a option?