The consumer ESU is ending in 4 months. LTSC isn't now, never has been, and never will be for consumer use, it is for OT usage - plant machinery, medical devices, manufacturing equipment etc. LTSC requires a Microsoft EA. You can't legally obtain LTSC to run on your PC at home.

Hmm actually looks decently interesting!  

Being on GitHub doesn't make something safe. Like any unofficial scripts to do x or y this caters to people with just enough knowledge to be dangerous. If you want to do what this does, and you actually know what you're doing then write your own script (or maybe just add the reg keys yourself) if you don't have the ability to read and understand what a script is doing, and especially don't run it with elevated privileges. Or in this case just use an MSA, sign up the normal route, and stop trying to push water up hill