Yeah, just clone AOSP, edit the source, spend hours fixing build errors, wait hours for the GSI to build, unlock your bootloader and lose all your data, flash the GSI, spend days creating shims to make vendor-specific features work properly, and finally profit. Easy.
I don't think Microsoft can reasonably block opening the command prompt and bypassing the OOBE without breaking a lot of other things, but them removing the simpler workarounds is a pretty obvious attempt to get more people to sign in with a Microsoft account.
Microsoft does sync activation keys to your account but the license is also embedded in the firmware in recent prebuilt laptops and desktops, so you don't need a Microsoft account to activate.
The article is talking about the initial setup experience, where you could put in a fake email to bypass the requirement to sign in with a Microsoft account.
If they're doing that, they're playing a very long game.