For all the handwringing that happens over modern console firmware updates, very little has changed in the "I just want to turn it on and play games" space.
While I'm willing to concede that PC gaming has it's place, the superiority complex PC gamers have is really toxic.
The two points you singled out highlight that there are bigger problems here. You didn't read that I'm more interested in having a relatively tiny machine I can have sit somewhere, relatively little power at peak with very little noise that's tightly integrated.
I just want something to turn on and play. Citing that joypads suck for games always gets me angry because we're expected to just accept the idea that every game is an FPS where that kind of input scheme is necessary. Same with "Well our games look nicer." Well, maybe. Sure. But at what cost? What's the power consumption? What's the thing like living with?
I used to be a PC gamer and it just wasn't worth it. Appliances that play games and only play games have a place in the market because some people just want to play games and not have to fiddle with shit to make it work. Don't try to tell me it's not a thing anymore, Valve recently shipped out an update to CS:GO on OS X that broke. In order to make it work you had to uninstall then reinstall.
Maybe someday there'll be a glorious day where consoles literally are just gaming PCs with fast on and off and the binary that runs on a PC is the same binary that runs on a console and everyone's happy. But we're not there yet. Sure, both the XB1 and the PS4 use SOCs from AMD that run x86 but the OS right now is tuned specifically for games and entertainment.
SteamOS isn't it because enough of the underlying OS is still visible to both the user and the games that if a rogue process makes poor life choices, your day will get worse. I haven't used SteamOS since it's release after playing with it a bit, so this may have changed.
However, I don't think it has. And I don't think now is the time. Nor do I think Valve, which has had issues curating their own store(see: Flight Control; Hatred is another issue entirely) or releasing games they've promised on time.