Yes, I see, have read that somewhere before, but sometimes it’s hard for me to find a post I read some time ago. 
Indeed. That’s an issue. In Windows terms, an AppImage is a “Portable” application. Meaning, you can take it anywhere, but it’s not integrated into your OS well. You need to manually create shortcuts, etc. Or use a tool for that, adding another layer in the wall of things a user has or might need to do.
Actually, that’s what Linus said in the talk I posted earlier.
For those who had not seen it yet:
He mentioned this explicit example of how package management on Linux distributions is most of the time a mess. Even if you create monolithic binaries, that are supposed to run anywhere, just like AppImage, there are distributions with different fonts, different paths to icons, etc… And you cannot account for that, even with AppImage, apparently.
Precisely. This is a huge problem. It’s also the result of many Linux users’ anti-n00b attitudes.