I guess a good niche usage can be showing pictures from digital camera (or phone connected as USB mass storage, or an arranged folder of pictures, or on the Internet), although 16:9 is annoyingly wide.

It's something I can imagine "normal" people to do. Unless you use a computer or device with 1080p or less output, you stand a chance at seeing the additional pixels/high res.
Otherwise 4K might be used to read text on the TV (web, pdf, txt, ...)

All the TV OS are sleazy and untrustworthy - you might as well buy your TV from Real Player or the Ministry of State Security. So there might be a need or demand or opportunity for a Free OS. Let's say, Ubuntu and Firefox OS are in a good position to provide such a critical software infrastructure. Oh wait!!! No they're not, the basement dwellers and their angry rants won. There's no safe OS for a TV (though maybe you can look at a picture gallery off-line)

GTK2 Nautilus is included in RHEL 6 :)

Otherwise, in MATE desktop it has moved to GTK3 and so it's GTK3 Caja rather than GTK2 Nautilus yet it's really really close. It's maintained plus a handful features such as closing tabs with middle click. GTK2 applications ported to GTK3 but keeping the UI traditional are a minimal disruption.

Related is the problem of the / partition filling because of the APT cache. You have to go delete the cache yourself. More funny if your / partition contains /home as well and there are zero bytes left (more likely than not if you installed on a 20GB or 30GB drive and tried to do the right thing by not partitioning excessively)

Amiga CD 32 with external keyboard would have been another option.
It was blockaded from reaching the US because of a XOR cursor patent!
This is what killed the Amiga 1200 and Commodore outright more than anything. It would have sold millions and would have made the A1200 a bit more relevant anyway.. as till Commodore's death Amiga games only targeted the A500.
Maybe the A1200/A4000 family would still have had a hard time against the 486 DX 33 and 486 DX/2 66 with Sound Blaster and VLB but with the console version killed in the egg it's hard to know.

It would have to use gaming laptop components, or up to 65W desktop CPU and mobile version of GTX 1080 or some GPU board small enough and not too hungry slanted sideways on a PCIe riser.

300 real watts in that form factor seem a bit much! That might be loud, and the power supply and heatsinks alone will be heavy.

If it ends up looking like an Apple III and weighs as much as the ugly tower this might ruin the point.

There would be a 150-game pirate cartridge made even before the adapter is available :)

If parts of the CPU reach 80C but it never crashes and works for 20 years, I don't see much wrong in that.

It can also run Windows 10 and get access to the Windows Store library. Just kidding here but access to the Android library might be precisely what we do not want. Millions of clones of pay-to-win games, etc. I don't want to get a controller in my hands, scroll a 250-page list of crap and waste $0.99 on something useless or ad-ridden.

Ubuntu would be interesting, they could also eventually bring their Atari game store to Ubuntu desktops/laptops (although there's support costs. I suppose they could require Wayland, which will prune old versions, unsupported drivers). There could be a way to run it in Windows (port the games outright, or just let nerds run it in a VM or Windows 10 WSL). Or they might just not bother and concentrate on making their console work right. Cross-platform games can be cross-platform games.

For a small fanless home console with no other particular defining feature? What about $99. Could be what 3rd world, Brazil etc. are looking for. Places that run on a solar panel and 4G, because their nation can't afford $200 billion to invest in power grid and fixed data network. Even in the 1st world, 10W kids machine is cheaper to run than $300 200W bro-gamer machine.

Importantly x86 gives you about the best GPU drivers. This will be either Intel or AMD, perhaps Intel is not really great on that front but not really bad either.
An nvidia ARM chip also gives you a top notch GPU driver but their one current chip's production, the Tegra X1 goes entirely to Nintendo Switch surely.

Android gaming on phones is a thing so I suppose you can get something workable there also, but you will be stuck to a particular Android version or a couple ones. We have enough Android crap as is and the Android SoC vendors aren't known for decade-long support. You can do custom google-less Android but with low end x86 you can easily go linux or FreeBSD as well. Yes there's linux and FreeBSD on ARM SoCs with 3D acceleration and such but outside Raspberry Pi and Nvidia Tegra it looks like a wasteland to me, am I right?

Or more accurately no 3.5mm jack. You can add a USB DAC perhaps but if this is a small, low end low power console we won't necessarily connect it to a proper TV or gasp, an oversized overpriced AV receiver.
It could go to a monitor, or a video projector, or be used as a music player so easy cheap audio out is welcome if you can put it in, thanks.

Beer/soda can can be cut in some simple way and used as a small burner for alcohol fuel.
This should make feel warm?

In my western european country I can recycle them by throwing into a special street trash can for non-glass recyclable shit but there's nothing to be earned.
Beers in glass bottles are a strange affair : you throw them in the glass with everything else. No deposits. Except for Belgian beers, which have a 10c deposit! and that works in a few dedicated beer shops at least. (the other thing that's known is coke bottles, but only bar/restaurant staff deals with that)

I want to agree fully with your rant, but the multi-touch screen made it. The pinch zoom gesture to view pictures and full web pages is maybe the defining feature.
Also, older wifi was about obsolete by 2007 (802.11b or WEP)