[nickjj]

> there’s a ton of non-uniqueness in that approach for a platform with millions of users

Sure but context is everything.

Chances are millions of users aren't all posting in the same thread / post / chat room / etc. at once. There might only be a few dozen or even hundreds of them, and the odds of hitting 2 people with the same name + similar color are really low then. Plus on top of that, some users will have custom avatars they've uploaded to make the sample size even less for running into a collision.

Google also happens to use the random color + first initial pattern too and they have over a billion users. It works, even in a busy Google Doc.