Blizzard literally said that there is no solution other than transferring a few weeks ago, absolutely nobody is surprised by this development.
If any company providing a service tells you "if you keep showing up during peak hours, expect long wait times" and you still show up during peak hours + complain about it, then that's frankly on you.
Who broke what?
The issue here is that you frankly do not behave like a functional adult should.
Yeah, sometimes everybody gets the short end of the stick, it happens, but when something inconvenient happens to you, then it's just bloody annoying to turn this into a blame game and tell them to fix this (despite the warning from that party that will absolutely happen) rather than take any alternatives on your part to avoid it.
The reality is here is plainly, most people aren't server engineers, nor have any understanding how Blizzard set up their servers, i cannot (nor the majority of people on this site) provide reasonable technical insight into this matter.
So when Blizzard says "there is no technical solution to this problem", then i'm frankly inclined to believe them until a person of expertise can reasonably disprove their statement.
Blizzard without question carries quite the blame in this situation as they let the mega servers grew to this size, but that's another story.
But i agree with you on one thing: This talk is done, at least on my part, because it reminds me too much of work when i have to put up with coworkers like you who aren't thinking about solving a problem but thinking how they can avoid working on the problem.