For the past several months, I've been running a bit of an experiment- running Ubuntu 18.04 from a 16GB USB 3 stick, and Steam/Proton on an additional 128GB USB 3 stick. Two USB sticks, an Intel Core I5-2500K, an MSI Lightning GTX-780, 8GB of RAM, and that's it. The idea was to see if, once and for all, Linux could be a true "daily driver" OS/environment for me. Before this, gaming was my one hangup with Linux. Wine could be pressed into service, but to get any particular Win32 app to work often took more effort than it was worth. Play on Linux was certainly a step forward, for non-Steam games or applications, but Steam with Proton makes using Linux for gaming as simple as pie, with few bugs and little noticeable drop in performance in games (which for me are mostly Bethesda ES/FO games). I've had to fallback on my Win 10 installation only to back-up/sync my iPhone before an OS upgrade, or to access my Windows stripped array to get to old files. If you told me 18 months ago that I would be booting into Linux daily for work and play, I'd have said you're daft. Now, however, I've come to appreciate the simplicity and utility that Ubuntu has to offer. Fully booted, at idle, it uses a mere ~800MB of RAM, and the processor is practically comatose (as an aside, there was a time, of course when even 1GB of RAM seemed to be fantasy to me, having been brought up on a fully loaded IBM PC XT with 640KB of RAM and 10 MB double-height 5.25" HDD).
Having said as much, if/when Ubuntu drops support for x86 to make life easier on its talented and dedicated developers, I will be forced to go back to Windows, and not be easily tempted back. Even Microsoft, some day, will decide to drop support for x86 (without VMs/Containers, etc), but I actually don't see that happening in my lifetime. Steam OS, which is also based on Debian, could prove a viable alternative for gamers, but only for the narrow focus of gaming, not being an every-day OS you could easily fool your mother into using. The entire point of Ubuntu, I thought was to create a version of Linux that would not frighten away the casual user, and would be as easy (or easier, in my experience with 18.04) to install and use as Windows. Dropping support for an entire, still widely used, architecture is certainly a step backwards. Saying "Run it in a VM" (with the necessary performance loss, if it runs at all) is the wrong message even if it's something as trivial as gaming. If it's not a turn-key solution, it's not going to be an easy sell as an alternative.