If this was going to be released imminently, I'd probably be annoyed that I've just built up a SFF desktop with vaguely similar specs.
Eurogamer/Digital Foundry have a good breakdown of it's hardware, however I suspect the secret sauce will be in the customisation of the CPU and GPU, as well as the software for the Steam OS. Nintendo have shown that it's possible to get well over-the-odds performance off lower-spec hardware with good optimisation.
I'll be really interested in the final price. Looking at the SFF build I did;
- Remove the OS cost (which I didn't pay) - less £170
- Half the memory - less £120
- Half the storage - less £115
- CPU's are very similar in core count/clock speeds
- Similar GPU, but half memory (8Gb vs 16Gb...AMD offer the 9060XT with both memory counts) - less £50
I'm going to assume it comes with the Steam Controller. A similar Windows controller (XBox one, which is what I use, and had previously for laptop gaming, and is the best-integrated into Steam) is ~£50.
That would put the self-build cost for a similar spec Windows machine at ~£1,300 for the 2Tb version....but in a case significantly larger (maybe 3x larger...and the Fractal Terra I used is a fairly small case for a PC). That's obviously way too much to compete with XBox/Playstation, which is the target market here. You can get a PS5 Pro for £700, and an xBox Series X for £500. The top-end Steam Deck is currently £569, so you have to assume a target price must be £700-800 max to draw the eye of the console-gamers.
If they can hit that (even with the lower spec one with 512Gb of storage), it would be an absolute steal, and not just for couch-gaming...assuming it could dual-boot into Windows, this could easily be a single household computer. Memory and Storage can both be upgraded.
The only real limiting factor I can see is the GPU memory of 8Gb. When I was building up my desktop, there was a lot of reporting that 8Gb of VRAM is not enough for modern gaming, so I ensured I got a 16Gb version for future-proofing, even if the card itself was below top-tier performance.