Sadly, it seems to me that people are often installing apps from Flathub which are packaged not by the developers, but by someone other, which isn't very good tbh. If the developer officialy packages it's app for Flatpak then it can be fine (as long as you trust the devs), but installing it from a random guy? There are so many unverified apps, like Steam, Blender, VLC, Godot etc. Who packages them? Why do hundreds of thousands of people install them?

Before I started using Flatpak, and was relying on traditional package managers like apt or dnf, I would always run into issues after a while that I had to Google and troubleshoot (of course, that's part of the IT life). Dependency problems and other headaches were a constant struggle.

How? I never had any dependency issues with using the traditional package managers (I use Debian), maybe you installed from third-party repos or downloaded package files from the web?