I think you would struggle to NOT build a more performant PC for the same price.
https://pcpartpicker.com/list/brbFsK This is $50 more but it has 1TB of storage and a newer generation of both CPU and GPU and will absolutely destroy it.
I'm sure you could get actually easily cheaper and better even, I haven't followed the market a lot lately.
Prebuilt are likely to be even better deals because they will use some cheap noname parts for the RAM and the PSU, which is mostly fine.
For me, size and aesthetics play a role. A PC like that is huge and, imo, much uglier. I know a lot of people do not care but I am sure I am also no the only one.
> A PC like that is huge and, imo, much uglier.
It's not huge, it's a mid-tower (admittedly, not a pretty one). But the real benefit is that it is upgradable. Basically you are trading off user serviceability for "it just works" and the form factor.
Another thing the Steam machine has is HDMI-CEC support, which is nice if you intend to use this with a TV, perhaps with KDE Plasma Bigscreen. But $1000 is rather steep for a console/HTPC.
Yeah, I know that for a lot of people that does not make sense, and I understand, but it does for me.
It's still missing wi-fi, bluetooth, sc dongle, sd card reader, (frugal) led bar, the hdmi cec functionality and whatever you value yourself for assembly, installation, troubleshooting and tweaking time (between half an afternoon to a whole day). Dealing with pc bioses is tedious and tweaking fan behavior and thermals could take a whole other day, which you are gonna need because the cheapo case you've picked up only comes with a single loud fan and poor ventilation for pc case standards, so you either gonna have a loud motherfucker or a cooked to perfection unreliable rig.
Let alone having to put the PC on the floor because it won't fit anywhere else in the living room.
I would have probably picked an Intel B580 for the additional VRAM (at $250), and a case with better airflow like the Bequiet Pure Base 501, but your point stands.
Even with similar specs you can still get more performance from a PC because Valve is throttling the Machine to keep thermals down.