Linux

No, because I don't have a very powerful computer

Even if I did, I would still prefer to have native applications because it would be more permissive

For me the perfect example is GNOME Builder (I use KDE Plasma) but this package has it all. No, you dont need to download any dependencies, the sandbox handles it all!

I didn’t like them before I used flatseal. Now I love them.

Flatpaks are my second choice when there isn't a recent enough version in the repos. They're fine but take 1. too much storage space, and 2. are usually slower

I like containerization for server applications, especially when running different services on one box. For desktop use, native libraries are stable and usually the applications being used are single instance. I don't see a point in running desktop apps in containers.

yes

In place of snap OF COURSE.

I can state without any doubt that i had problems with 80% of the programs coming from snap..

I use flatpaks mostly. Flatpak dependencies (runtimes) are stored separately from the host system so and don't bloat my system with unwanted libraries and binaries. App data and configs are stored separately and better organized. Everything runs in sanboxes. I use overrides extensively. All these are very convenient for me.

I haven't used any flatpacks, mostly because they don't seem to have a good solution for running terminal programs. (Also I don't like that the application developer chooses the permissions to expose rather than the user.

However, I have been using bubblewrap which is what flatpack uses under the hood to sandbox. This allows me to run both gui and non-gui programs, and I have the control of exposing the minimum required permissions that I'm comfortable giving an untrusted piece of software.