To be expected tbh. Beta is normally a relatively small number of invites over the course of several waves, only getting to have the most players toward the end as a form of stress testing.
They let people buy access so there’s just a TON of people who would normally just not ever have access all there from day 1.
I think they did this one other time, I wonder if it was a mess back then too. Was it MoP? Idk.