I love it when I learn new stuff about Group Policy; or when someone shows me stuff I did know in a unique way. This is one of those.
Microsoft has a great blog entry and corresponding spreadsheet to demonstrate “What settings were added or subtracted in ADMX thru the years”?
The only time to really “worry” is when Group Policy ADMX settings are DELETED by the product team. Typically: This isn’t done.
But it CAN happen; and if it does, you can set-GPregistryvalue Powershell item to help negotiate those rare cases.
(I go over this in supreme detail in my LIVE training class… hint, hint.)