Windows 10 and onwards (and back to Windows 7 to an extent but not as much) will periodically check the license authentication and deactivate keys which have been blacklisted due to inappropriately shared volume licenses, etc.
Thanks for the info, my Windows partitions are only used to play games, bar an old laptop which is used for car diagnostic software out in the wild so is never online, so I didn't know that

The rig in my sig for example is purely a gaming PC that lives under the tv - and only ever turned on to do so, the only other Windows install I have on a PC (excluding the aforementioned laptop) is a dual boot to literally play CS2 when I CBA on a MacOS system at the desk
I think in my use case, I'll just see how it goes, I only paid a fiver per retail key, off a site that seems to have done me well for the last year across 3 systems.
It's a shame they don't take a leaf out of MacOS' book and make it legally free direct, even for a Windows Home version I think this should be the case, with no telemetry or nonsense!
I remember years back when MacOS did charge it was something tiny like £36 then each time i upgraded seemed to go down around £10-12, then it got to a point where they just decided to offer it free, and all that time you could legally use it on upto 5 machines in your household, with zero registration required nor telemetry, nor ads, now a days you can optionally provide feedback/telemetry IF
you like, but it's not madatory.