Well doesnt change the fact that Heavensward release was smoother. That WAS their first expansion, so you might had thought it will be huge problem. Best part was that Data Center back then was still in Canada yet it was more playable than on this expansion and with Data Center actually in Europe. 90002 plagues people, but what most piss them off is fact that they need to wait in queue that is around 1500-2000 people to come back.

Dont get me wrong. Yoshida and crew made awesone expansion (as far as Ive explored), but technical side is a total failure. Unprepared for huge load on server nor they did not take notes from Heavensward early access. They could had ceased Palace of the Dead for time when there will be high congestion of servers. Let is spread out and then bring it back. Its the technical crew at Square Enix that did not prepared for Stormblood Early Access plus add 10-20% more extra room for servers to breathe just to be on the save side.

Only way to make this playable is to play between midnight and 8-9am or when people are at work.

TL;DR
I dont blame Yoshi and others or demand refund/free sub or (by the Thals Balls) "Fuck it, I unsub" (We're just small numbers to them), but on technical side they were not prepared yet they had experience from previous expansion and seen problems arising on other MMORPGs launches.