Just wanted to say, I am a software engineer, and your concerns are valid.
The user experience is surely something Steam wants to improve, and I expect they will iterate both on the current software and future hardware revisions.
I don’t think anyone other than Valve will know why they don’t have the desired functionality. The answers are usually long and boring for this type of problem.
Surprised we haven’t seen launchers adding native support for Linux. You’d think they would want to take advantage of the millions of steam decks on the market.
Perhaps they are busy contemplating their own hardware investments, which will surely flood the market with cheap and poorly constructed knockoffs.