Steam UI genuinely fucks, and if you're suggesting it should be homogenized into the bland, emotionless material design full of dark patterns that every other web experience has turned into... then you, sir, can go to hell
Good design doesn't have to be bland, and what does this have to do with dark patterns?
IMO the desktop Steam client as well as the gamescope have some pretty confusing UI. Once you get used to it it's fine but that's the case for any shitty UI. Except Gamescope, which is buggy to traverse by controller (which is what it was designed for lol)
Steam is a bastard child of monopoly. They don't innovate because they barely have any competition.
And to this dya one cant fucking increase font size in Steam. Fuck them, I'm old, the letters are a little to small for me. Even fucking browsers allow for font changes, but not Steam. Fuck them.
Also a great VR Headset and the runtime used by this and many other VR Headsets. If anyone is actually innovating it's Valve. Everyone else is mostly trying to catch up to the features Steam provides.
Steam isn't just the client, it's also a ton of APIs (steamworks sdk) and services available to developers for integration with Steam, Steam workshop, distribution of updates, cloud save, multiplayer, chat, achievements etc.
No other launcher comes even close in terms of functionality even if the UI isn't perfect.