yes, Rush 2 Recomp was made with AI. There are good and bad uses of AI, and I am not sure how I feel about recomps. We probably wouldn't have any Rush recomps without it, so I think it's okay in this instance. You need your own copy of the game to add Rush 1 and 2049 content. They won't share where to find those, you have to dump your own copy or find backups yourself.
Honestly, that project mixes all the content from all three games together which is why I created PJSF in the first place. I started this project before AI could recomp games, before Rush was getting much attention in that regard. It basically fills the purpose of what I wanted PJSF to be, so I am not sure how to continue.
If PJSF continues, it'll probably be to make a crazy custom content branch of Rush and give people a crazy modding platform for racing games in general. That's the only way I can see PJSF needing to exist, between that and adding the arcade-exclusive content. I am not sure if the Rush community is large enough to support that many different versions of the game spreading focus out in different directions, Rush is not exactly as popular as something like Mario64.
I'm going to keep focusing on Mach1 for the time being and I'll decide what to do with PJSF when that's finished.