Flatpak and Snap definitely make installation more simple. The packages come with their own dependencies so you have way less issues with conflicting dependencies. I like them when they are officially supported by the distribution or developer, but I prefer the official installations over supporting a random person making a package (not sure if this is a thing with Flatpak, but with Snaps that was definitely a thing).

Some software really benefits from not begin inside flatpak though, I had to switch back to the deb version of Visual Studio Code as the integrated console didn't have access to some software outside the package and was also logging weird errors.

My experience with Flatpaks has been so stable and hassle-free that it motivated me to switch to Fedora Silverblue.

I prefered AppImages, but now that I'm on Nix, I've gone back to native. Native packages work well in the NixOS ecosystem.

I'm running Ubuntu now and I'm in Snap hell.

It works well enough for some very basic apps, but for me personally, Snap has created far more problems than it has solved. With Firefox, for example, it makes it a lot harder to use some extensions, and FileBot is entirely useless without file system access (I mean, that's the entire point of the program).

I've heard Flatpak is better but my experience is somewhat limited. It could hardly be worse, though...