It's Valve hardware, so more likely than not it'll flop and you can pick one up for $50 on the 2022 winter sale. Even then it might be relevant for enough weeks to make devs consider designing for native Linux and be in too deep to back out.
Speaking as someone with a steam link and controller floating around their house.
I wouldn't mind it flopping an having the option to get it for 50 buckaroos :). But that's highly unlikely.
Even if it fails as a portable gaming platform the hardware sounds very decent and I wouldn't expect them to have Apple level margins on those.
I've skipped the link/steam machine because "livingroom entertainment" isn't my thing, but I was pleased with the quality of the Steam controller. Although I would have liked them to be bold with the design and keep just the original prototype (without thumb stick/face buttons) (wouldn't have minded a novelty controller that works well with just a few games).
Speaking as someone with a steam link and controller floating around their house.