Earlier quoted context omitted.
I have to use Windows once in a while (circumstances). Best way to forget about the existence of spyware (aka telemetry) that I found is to not connect a Windows box directly to internet. I configured my router to give it a gateway and DNS IPs which don't exist in the network. Eat that, Microsoft. And I can still connect to internet by manually setting a SOCKSv5a proxy to the router in Firefox and other software that…
Since the 21H1 update you might start noticing connection drops since a new wlan autoconfig feature has been added: if windows can't ping home reliably, it will restart your nic. Yep.
[1] https://wiki.archlinux.org/title/NetworkManager#Checking_con...