Debug bluetooth option not available

I’ve heard that it was removed in Monterey.

You’ll have to use the terminal or the plist deletion method instead. You can see this blog post here for guidance: https://macreports.com/how-to-reset-bluetooth-in-macos-monterey/

I agree that it shouldn’t have been removed: https://www.apple.com/feedback/

Restart your Mac first then.

Did you go to the correct library folder? There is one within your user account, and one outside of it, at least on my Mac.

I don’t know what to suggest then. The file is definitely there for me on my Mac, as it is in the tutorial.

Just do the terminal method instead, since you can’t get the other one to work. If it frustrates you, you should try calling Apple Support or going into an Apple Store or AASP to see if they can help.