When signing in on the Apple Developer website with the phone number-based account I created when I was setting up my Mac, this error message is shown: Your Apple ID is not eligible to use this application at this time.
I've seen other people with this problem and I hope that we will be able to log in using phone number accounts soon. For now, creating a new email-based account seems to be the only solution, but I don't want to do that 😂