So, I'm finishing up T&T.. and I'm wondering if it would be a good idea to skip the second trilogy and just play investigations and TGAA. All my friends don't speak very well of the mainline after the third game..
What do you think? Would the Apollo trilogy still be a good experience even with games that are clearly inferior to the previous ones?

It's a hard question to answer because I think Apollo justice is an experience worth it on its own due to being very unique and having some of the greatest atmosphere in the series, but DD and SoJ have a myriad of issues and don't have those pluses to them. It's totally fine to skip the latter trilogy and play GAA and Investigations but I do encourage still playing at least Apollo Justice and only really playing DD and SoJ if you really want to.

SoJ has a lot more redeeming about it than DD does, but they're not nearly as strong as the rest of the games.

Real ranking. I need to finish Resolve soon...

I think it's a good idea to give it a try. If after playing AJ I still don't feel encouraged to continue to DD, I will make that decision, thanks.

Your profile is extremely based, by the way

Thank you! I hope you like AJ it's super unique and grew on me hard since I finished it!