How important is the "reuseport" flag for quic?

[Dominic Preston]

I'm using nginx 1.26.1 from the nginx.org ubuntu repo.

I find when I remove the "reuseport" flag from the "listen" directive
for my quic port, a lot page assets fail to load, and the browser
ultimately falls back to http/2.

When I re-add "reuseport", all http/3 requests succeed again.

How crucial is "reuseport" when using quic on nginx? Is it normal for
things to break badly without it?