Indie developers typically want to design, well, their own game. Their own vision, art, music, mechanics working in concert. I don't think anyone is dreaming of

Indie developers typically want to design, well, their own game. Their own vision, art, music, mechanics working in concert. I don't think anyone is dreaming of creating a showroom for a bunch of random other assets out there in the world. Asset-store flips are already considered jokes. Original, boutique art in an indie game will always win out and stand out. They'd still need to do the work to implement every single item you are talking about. No indie would even want to do that. Nobody goes indie to work on compatibility drudge-work. Maybe if they are trying to jump on get-rich-quick financialization trend, but not if they want to actually work on their art.