I've a Gigabyte motherboard on this pc and an ASUS on the other pc that has this issue. So I don't think that it's motherboard specific.
I have a bit more information too, though:
I just uninstalled the only 2 possible updates from the pc it asked for me to restart and I didn't, cause I was watching some twitch stream and out of a sudden, it started doing it 6-7 times one after another, I had time to start the diagnostic apps that I have [ProcMon and USBDeview] and I logged the operations and I was looking at the voltages on the USB Ports. So the USB power just disappeared for the period of the "off", I know it's logical but at least it didn't show that they were overcharged, so there is something turning them off. I have to check now the huge 21 million operations and filter out for the timeline that the disconnects happened, and see if there was a trigger operation or not. So, uh... I'll get back on that.
There are still updates that have been made in 8th and 18th of June for me, that I can't uninstall [at least not with the default add/remove app from windows]. But what makes me ponder quite a bit is... that it's not a recent issue. There are posts that date back to 2020 if I remember correctly, which means that it might not be an update issue but something else.
My following tests will be, to check the said operations when the disconnects happened, maybe I see a pattern and if that doesn't make any sense I will try a Linux LiveCD Distro for a day or two to check if that still happens.