OK, I know I just said I wasn't going to do this. I've "finished" migrating my server to a new AMD Ryzen 7 3750H based host machine running Windows 11 Professional.
While it looked initially like the previous Intel Haswell i5-4590T host was going to run Windows 11 just fine - it did not. It was fine most of time, but the biggest issue was it wouldn't reboot. It would be stuck in the shutdown sequence forever and require that I hold down the power button, which turned into a real bummer following Patch Tuesday.
I did a side-by-side migration, moving each service/application one at a time over several days. The first (and easiest) thing I moved over was the Windows 10 BBS Hyper-V virtual machine (have to love VMs). However, I did things a little differently.
With the stupid easy VM migration top of mind, and with 4 cores / 8 threads to play with it, I decided it was time to bring back a Linux VM (Ubuntu Server 20.04) and migrate some of the stuff to it rather than on Windows. Ghost CMS was an obvious choice for one - it runs on Windows just fine, but it isn't supported for "production" on Windows. This was most painful earlier on, upgrades previous to 3.0 completely trashed the site and I had to start over (*every* time) - the upgrade script was looking for Linux stuff and painfully failed every time until version 3.0 came out.
The Lounge IRC also made the move to Linux, because like Ghost it's Node.js based and made sense. Again, it runs fine in Windows, but the config files get stuffed in a "strange" location, and (like Ghost) it doesn't run as a service - batch files loaded it at the (automatic) login.
Roundcube also moved to Linux, mostly because I remembered it took some doing to get PHP running with Nginx on Windows, and it seemed like it would be faster to spin up on Linux.
Again, with the stupid easy VM migration top of mind, I've also spun up a new Windows 11 Virtual Machine to run hMailServer, Nginx, fTelnet and some supporting software on Windows. With this 3rd VM that seems to come close to maxing out the 16GB of RAM of on the system a good bit of the time.
So, the new Windows 11 host is really just acting as a Hypervisor at this point. Honestly, I was wanting to try Hyper-V Server at one point - however, since Microsoft discontinued it after the 2019 version, I'm guessed that I was better off just running them off Windows 11.