I would appreciate a link to the details about 'setting a flag.' The last version of that I used earlier this year stopped working in recent months, and I believe I saw tech news stories to the effect that Microsoft had intentionally closed that path.
For now I just use a customer-supplied email address which I used to setup a Microsoft account, setup Windows and use that account, immediately create a local-only 'admin' account with full rights, delete the online associated account, and start creating user account(s) from there.
I just recently had to install Windows 11 fresh on a computer and this is what I used
https://rtech.support/guides/bypass-11/
I have a Microsoft account, but I prefer to use a local account to avoid a lot of the "value add" that comes from using the Microsoft account.
I had recently had to install windows for the first time in years, did some chatting with mr gpt and poking around on reddit until I arrived at: https://massgrave.dev. They guide you on how to download windows LTSC from the "official" Microsoft links. So much less crap shoved down the system, it's kind of nice.