On Pro it would be better to use the group policy editor. As a bonus this also ensures the setting survives updates, which is not always a given for raw registry edits.
If gpedit.msc gives you unexpected results (I.e. policies just don’t seem to work) then do two things:
1. gpupdate /force 2. Download the latest ADMX templates; newer versions of Windows often introduce similarly-named - but still distinct - policy templates, for unwanted “features” in older versions, just like Start Menu web-search and forced-restarts for updates.
Lastly, while Windows LTSC is really what Microsoft should make available for everyone, don’t forget that Windows Server is still Windows LTSC too - so if you’re outside the MSDN Subscription Garden-of-Eden, you can still get Windows Server tricked-out as a real LTSC Workstation OS.