I think what's special here is:
1) Full compatibility with SteamOS. You won't have to fiddle with drivers/hardware/whatever to get it working[1].
2) The physical hardware is maximally condensed, more so than you'd be able to do yourself with a SFF build.
I'd have definitely considered this if I wasn't already doing my own SFF stuff. Gaming on the Deck is a delight and I'd love that console-esque experience for my primary gaming PC as well.
[1]: Incidentally, it looks like they're working on broader support. Sweet! https://www.theverge.com/games/953411/valve-steamos-desktop-...
> I'd love that console-esque experience for my primary gaming PC as well.
So does the typical gamer who's not a nerd like GP. I'm not framing it as an insult, more like a reminder: we infamously ignore the power of brands and sensible defaults chosen for you.
I'd word your first point a bit more strongly:
The Steam Machine is the best of both worlds, yes, it is a plain PC and Valve is recognizing that. However, they are also selling a fully supported Linux gaming rig that plays many Windows games out of the box.
That might not excite everyone, but it does me.