I have it installed on an old 2006 MacBook, so Microsoft was still providing updates for a 12 year old machine... one that Apple itself abandoned after just 6 years. It's one of my favorite examples of Microsoft's longer support for old hardware.

And for what it's worth, after 12 years and 3 Mac purchases, I've switched & just bought a PC again.

I considered the Surface Book 2, which has an excellent keyboard & trackpad, but the SSD can't be replaced by the user & tops out at 1TB. I was worried about the Surface Book hinge being fragile in my backpack while travelling & commuting.

My 2006, 2007 and even my 2000 Pismo G3 Macs all still work well. I used to love Apple reliability & recommended the Apple Store to everyone, I was that guy who queued for a day-one iPhone 4. But my mid-2012 MacBook Pro (bought in 2015) has been a lemon, the data flex cable keeps failing every few months, causing it to corrupt data & eventually lose the boot drive. (SuperDuper! has been a lifesaver.) Apple have replaced the cable 5 times now, each time with a week of downtime, but the replacement cables all have the same known defect & I just can't trust the machine anymore.

I'm not much of a Linux user, but I've been trying elementary OS 0.4.1 Loki via Parallels and like it a lot. Unfortunately elementary OS 5 Juno has been buggy for me (random black screens requiring a reboot), so I'm stuck on Loki for now.

I was tempted to put elementary OS on my 32-bit 2006 MacBook (the one that currently has Windows 10), but there isn't a 32-bit version of elementary OS anymore.

I'm pretty pleased with the X1E: it's not quite MBP-level thin, but it's still a great balance of power and portability. NotebookCheck has a review that's worth checking out.

elementary OS feels fast, familiar, and refined. It's not quite as fleshed out as other distros like Mint (or macOS itself, for that matter), but it's getting better with each release.

The 4K HiDPI screen on the X1E is vibrant. My biggest concern was that the HiDPI scaling on Linux wouldn't be up to snuff, but I've been pleasantly surprised. The scaling for GTK apps was perfect right out of the box. There were some extra steps to get Qt apps to scale properly and inherit the GTK theme, but they look great now. Wine and Steam basically just required checking a box to get the scaling to work.

Happy to answer any specific questions you have.

I'd love to hear your thoughts on battery life doing anything useful (not watching movies) with your new one. I'm debating an X1 Carbon, HP Spectre, or XPS 13 to upgrade to in the next few months.

I'm more worried about screen issues. I got the premium HDR Dolby Vision screen, and I love the 500 nits & the wide color gamut is stunning & very OLED-like. But the calibration is off, the screen has a red-tint that hurts my eyes and makes the rest of the world look sickly green when I look away from the screen. I fear I'll have to buy an X-Rite and make my own calibration. It isn't like my Dell monitor, which came individually calibrated & with a printout of the calibration.

Also, this X1 Yoga (or Windows?) does lots of dynamic screen dimming, which was messing with Sublime Text in Monokai (dark) theme. It would dim the screen so much that white text would become mid-grey & it was unreadable & low contrast. I was able to turn that setting off, but doing so has reduced battery life to the numbers you see above.

If having a large / replaceable SSD wasn't a priority (and battery was more of a priority), I think I would very seriously consider the Surface Book 2. But hopefully I'll like the X1 Yoga more as I get used to it.

What's the cost/benefit of that? How much would it cost to build it and how much could they make?

You can theoretically do ANYTHING... but a business exists to make money...

Why does Microsoft support 16bit? because - without a doubt - someone is paying them for that "extra" support.

As I said... there are many reasons - and a company exists to make money.

If they decide not to do something that doesn't make them money? It's not a hard reason to see why...