When you launch the Steam Deck in desktop mode, the UI by default contains a shortcut to something called "Discover Software Center". My experience with Linux-based system is very limited, but I am aware that most distributions have a sort of software center or package manager like this, comparable to an app store. I have read that each Linux distribution has its own repository of games and applications, so I'm assuming the same is true for SteamOS. What I don't understand however, is how these repositories are managed and curated. Does the team or company behind the OS manually verify everything on it, or could theoretically anyone pose as the developer of some popular software and submit something malicious to appear in there?
The specific case that brought this question up for me is when I wanted to install Discord on the Steam Deck. I found it in Discover, but the app's description says "This wrapper is not verified by, affiliated with, or supported by Discord Inc." This has me confused, and there doesn't seem to be any further clarification about this. I am aware of third party clients for apps like Discord existing, but how can I be certain this won't steal my login details, or secretly run other things in the background that I may not want? Similar concerns apply to other games and programs.
Can anything in the Discover center be blindly trusted to be safe? If so, why, and if not, how would you make sure?