This was a funny one to read. I worked at Atlassian for around a year, focussing mainly on this onboarding process.

When I started, the provisioning delay was about 7 minutes and the loading screen was actually first just a 404 error and then just a static page saying something like "please wait while this gets set up" (no progress bar and no redirect on completion).

It's funny knowing that has been one of the biggest onboarding advancements and it's still being seen as a flaw.

That's probably true, but in most cases users don't think about how what they just signed up for is served under the hood, so there is some merit in this view.