No one is buying it over an iPad and iPhone. You can own all 3.
Why? Because the iPhone and iPad are both terrible at any sort of gaming beyond the basic genres.
This hinges on a lot of unknowns. We don’t know what a “Stevedeck” would look like or be capable of.
Would it just be an iPad with built in controllers? Then who would buy it over a regular iPad?
Would it be a gimped Mac?
Would it have its own App Store? Would it use the iOS App Store?
if it didn’t have access to games outside the iOS store I’d see the “Stevedeck” being DOA. And if we did, what’s the advantage of it over a Mac?
The biggest elephant in the room is that the GabeStation has Steam and Proton built in. Giving access to many more games than either iOS or MacOS. Unless Apple worked to build a compatibility layer like Wine, then I can’t see any Apple “gaming” device taking off.