Thanks a crazy lot for writing this as it actually made me genuinely understand the differences.

And also, I must say that one of the most underrated parts which you told which I didn't knew about was that apptainer can be "unisolated?" ie. we don't have to do crazy shenanigans for it to access my files and it can just do it simply.

Like someone else had mentioned https://nixery.dev/ and I wanted to see if I could use nix tools via docker and use them as if they were installed on my own system and apptainer really nailed it. I read that nixery.dev had to do some shenanigans to prevent the 150 layer or something but I suppose SIF doesn't have to deal with it so I am actually excited a little too haha. Thanks a lot!!

Side Note: I think that there might be better ways to run nix apps like nix-appimage but I am just trying out things because why not. Its fun.