The steam deck isn't even trying to be competition with the Switch. Its a mini handheld PC that allows Valve to leverage their eco system in a handheld device. I am not even sure why the switch comes up in the discussion. Besides from form factor that's pretty much about it between the 2 devices. This is purely aimed at the PC crowd which I might add is pretty big. It gives that group a pretty good piece of hardware in a handheld size and form factor and allow them to leverage their steam library. I also believe this is valve trying to get more traction with their Proton OS. If they are able to sell a good big of hardware, they can get more game support for their OS and thus build on that for their next iteration.