So this is how my low numbered account was stolen back in the day - thanks for sharing.
I feel like it's the same with your first phone number back when there were only landlines, etc. Some numbers are hard-wired.
I also remember my compuserve id which lasted a mere 6 months over 30 years ago, And that was 10 digits.
"What's your old password?"
"something_more_than_8_characters_long"
"Let me check. The result of the check is... ERROR. Great, what's your new password?"