Very possibly true - Raspberry Pi mirrors supposedly do that too, but I find if I manually select a local mirror like Yandex or True Network, my update download speeds increase dramatically.
Even if the CDN is perfect, (which I doubt), the ability to select an endpoint would give the end-user a sense of control over the problem which seems to be lacking. The user feels helpless and therefore gets upset.
If the user can see that every one of 87 different download endpoints are at 100% capacity, he might just say “I’ll wait until tomorrow” instead of getting bent outta shape.