I wonder (assuming the leaked specs are accurate) if the tdp was 30w if the switch 2 would outperform the steam deck or rog ally.
I find that super unlikely. The steamdeck is larger and has a fairly robust cooling setup and at full power it puts out a massive amount of heat. Nintendo is pretty hung up on user experience with their hardware (not so much with software and UI, but I digress) so I don't see them being comfortable with that kind of heat output.
That's also ignoring battery size. The steamdeck has a 40 wh battery so would last about 80 minutes from full to 100% dead (so less then 80 minutes if they use a sane battery management system).
What will end up being a potentially killer feature is DLSS. They could use a 1080p or even something a little bigger like 1200p or 1440p and then use a combo of DLSS upscaling and frame generation to take the load off the GPU while still giving excellent image quality and framerates.
I hope the whole PC portable rage going on now convinces Nvidia to take a shot at an APU type design for a steam handheld. I doubt AMD would want to partner up but Intel has some excellent packaging designs so maybe the could come up with a reasonably low powered intel/nvidia design.
That or AMD could add a tensor core style functionality to their next RDNA design and make an FSR that's comparable to DLSS.