This wouldn't have worked either. Lots of countries, where vaccines weren't widely available yet, were going through a huge Delta wave before and after WWDC.

Now that most places have vaccines, it probably doesn't make sense to wait for the next major release because this has already been long delayed.

Other factors could have also been at play - perhaps Apple Inc had a lot of internal tools on 2.X and has only recently gotten around to migrating all of those.