Also personally built a gaming PC this year, picked a Ryzen just for fun.
Right now, it's low-end gaming, I got a 3200G because the integrated graphics are adequate for the games I play. The PCIe slot sits empty, waiting.
In some years when AM5 comes out and AM4 chips get cheap, I'll look at the last/best of the breed and pick a new chip. It probably won't have integrated graphics, so at that time, I'll add a discrete GPU. I plan to have this motherboard and RAM for probably 15-20 years.
(Just like its predecessor, an AthlonX2 4850e, in an AM2+ board from 2008. Which I recently dropped a $30 Phenom into, and it's a relevant machine again, my workbench workhorse.)
So I can run the latest 3000 series with my current first gen AM4 board which is great. As you point out though the 16 and 32 core chips might be too power hungry for some boards.
I would love to see an AM4 3600G and 3700G though, basically a 3600 or 3700 with the addition of a GPU chiplet. There are plenty of people out there that could use more CPU but don't need a discrete GPU for work.
As I understand it, they aim the high-TDP parts at the enthusiast/gamer/workstation market where a discrete GPU is just a given, so there'll probably never be a 3700G. Darn!
AMD is finally showing life across their entire product catalog, and I couldn't be happier.
For Linux, it's been more than a pain, and pretty much have to install with a 5.3 kernel base os to begin with for it to work from the start, saw a lot of just black screens in the nearer term distros. When the 19.10 Ubuntu came out, it mostly just worked, then after an update, blank screens... same with 18.04 and the supported drivers.
On windows, a number of issues, reset, more issues.
Since around 5.4 kernel, and now on 5.6 rc, it's been much better, and the recent driver update for Windows has stabilized. Just the same, would have been better off with NVidia for the past 5 months or so.
I was planning on waiting until January to build, but was having issues with my old system (i7 4790K). So built out with an x570 mb, and 3600, swapped out with 3950X late december. Had a few issues with motherboard drivers as well (intel bt and wireless very bleeding edge).
At this point I'm very happy though. Just took a while to stabilize and wouldn't go bleeding edge AMD again, but would wait 3-6 months for any new chipset or gpu.
I'm not using latest Ryzen though so I wouldn't know what bleeding edge AMD on the CPU side feels like.
Aside, RGB support for linux sucks.
There seems to be large variance in the different 5700XTs. Some of the third party ones don't have adequate cooling and quite literally cannot meet their intended specifications, like the ASUS TUF line.
I have no idea how well it works on Linux
Although I have to say - the last gaming PC I made was about ~13 years ago and this made me hesitant to move to AMD. During the time I was 'gaming' (mid 2000s to mid 2010s) all the hype was intel..
I have hardware that is over a decade old, 'young' people scoff at anything over a few years old! But there's a sweet spot to be had where you can buy older, rather than ancient or new and save yourself a fortune.
That said, my latest console is a Gamecube.