Very few companies do this. Github and Twitter are some of the only ones. And they were certainly incredibly novel at the time.
Back in the 90's and 2000s, URLs looked disgusting. Remember this [1] nonsense?
[1] https://www.php.net/manual/en/session.idpassing.php (see "example 1")
That may be, but the user I responded to said "top level". Anyways, what looks disgusting about:
yourname.livejournal.com
yourname.blogspot.com
myspace.com/yourname
?
This was all before github, so objectively not novel by then.