I think it's very impersonal to have a random number assigned when joining the forums for the first time. A number like 28421635479, or worse a hash like f801628d-ffbe-4603-9cfd-eec4ee2b55ac doesn't help to feel part of a community, you are just a number.
Having a nickname instead could help people to feel part of a community and behave accordingly. I know they can pick one in the profile but they might not discover it right at the beginning.
The idea is to ask for a nickname at registration time.
If we don't want to bother the user, there could be an automatic suggestion based on the character before the @ in the email address. email@example.com would suggest bob. And if it's taken a number is added with an increment : bob1, bob 2, ... bob 8016, ...
But the field should be editable so they can change it to "Bob Foo" or anything they want. If possible with an ajax call to check if it's available in real time.
This would be a great advantage for supporters as well. We could recognize people posting regularly in the same Space. We could remember some of their previous questions that would give us some more context. Or we could remember that they never come back to give feedback on an answer and we could ask them politely to check their previous questions.
I think the nickname is a fundamental part of an online community, that's how you get better connections between people. It would also be a bit less anonymous so some people might have more respect as well.
And users can still enter an number if they don't want to have a nice username. But at least most of them would have something better.
PS : Sorry if it was discussed before but I couldn't find anything related to that.
PPS : Edited to add the suggestion to solve the issue it