I agree with this, but as an app developer, can I just say, Flathub’s documentation is an absolute abomination. It is so bad, that I’ve tried 3 times to publish an app and have given up each time. I can build a local Flatpak just fine, but getting it on Flathub is just so convoluted and bad.
AppImages are ridiculously easy to build and distribute, just a pain to actually use. And even then, they’re not that much of a pain.