I suppose if you're trying to get it to run the latest and greatest games that may require some tinkering, although it seems like an increasing contingent of games seem to be launching steam deck aimed updated and setting configuration.
I would guess my relatively anccient desktop i7-7600k and gtx 1080 is still a more capable gaming PC but doesn't fit as nicely in my backpack or in bed.
I'm not trying to hate on the steamdeck. I think it's super cool and would love to have one. But it's too expensive for me and I'm not sure they even ship it to my area. While the switch is super affordable and a just more out of the box works experience. I know every game I buy for the switch will work great on it, meanwhile I can expect most games I have on steam will not have great controller support or may not run well on the system so its a bit more of a "at your own risk" platform.
I paid $350 canadian for a 64gb steam deck and paid another $100 canadian for a 1tb 2230 format ssd (thats only $80 now). I think the canadian dollar is slightly more valuable than aussie bucks right now but not double as valuable. 1 canadian dollar is $1.12 kangaroo bucks.
So your evaluation of the cost of the steam deck is just wrong. Its way cheaper than you imagine.
Also, valve has put literal years into Steam Input, which lets developers set up controller support, and also lets you load community sourced controller setups for your games. The Steam decks touchpads also let mouse driven games work pretty amazingly in a way that an xbox controller or switch can't.
You're just kind of wrong about the input situation. steam has basically the most sophisticated input software you can get and most of the time it just works, and when it doesn't you just load a community setup and play.
Also there was a queue for the first few months, but now you can order it and get it shipped right away.
Also you can tinker if you want but you don't have to. Just play verified Steam Deck games and it's as simple as a Switch.
Why some people are so hell-bent on seeing the Deck fail is a mystery to me. Either they are simping for some company in competition with Valve/Deck, or they are bitter about people having fun. I could understand the criticisms of it, of which there were many upon initial release, but overall it's a pretty good experience these days.
While the steam deck is an expensive tinkerers device that’s usually sold out.