Here’s one possible method. Note it works better the more people use it.
Generate a list of 16[1] diceware[2] passwords of length 1. Pick the one that you like best. Try it.
If the username already exists, repeat with length N+1 until you get something that works[3].
This is better than ‘truly’ random usernames for much the same reasons that diceware passwords are better than ‘truly’ random passwords. It’s designed to be somewhat pronounceable and tokenizable.
Here’s one possible method. Note it works better the more people use it.
Generate a list of 16[1] diceware[2] passwords of length 1. Pick the one that you like best. Try it.
If the username already exists, repeat with length N+1 until you get something that works[3].
This is better than ‘truly’ random usernames for much the same reasons that diceware passwords are better than ‘truly’ random passwords. It’s designed to be somewhat pronounceable and tokenizable.
This parameter is tunable. 16 means you leak at most 4 bits of info here.
https://www.diceware.net/
Or skip directly to e.g. N=3.