The main influx of players that really pushed things past the limit was during the summer. They had already been working on the Oceanic Datacenter which was delayed to February 2022; so it sounds like some of their orders were delayed. Yoshi P stated that despite being willing to pay marked up prices, they were not able to secure additional servers. So this shortage is closer to a depletion of supply. Maybe this so called stock you speak of isn't compatible for one reason or another? Or maybe it isn't as plentiful as you think it is, perhaps it isn't anywhere near enough for the scale the game needs it to be.
Just comparing the number of players isn't the correct manner; rather you have to compare the growth rates. FFXIV had an explosive growth rate in the past year, surpassing all of their projections. They were not expecting so many people to move from WoW to FFXIV. FFXIV growth rate was unprecedented. WoW has lost players over years. Also, if you look at the server error tweaks, they are just bandaid solutions; they are simply trying to mitigate the issues as much as they can, but none of them actually solves the root cause because the solution to that is not a technical solution. All of these errors existed before Endwalker came out. What is the main difference between now and then? The number of people trying to log in and play.
Just because they can make some minor tweaks as a stopgap doesn't mean a technical solution exists. The root cause is a lack of servers and they do not have the means to get more servers due to the chip shortage. The entitled part comes from not taking into account factors like the chip shortage and essentially expecting people to somehow do the impossible.
There is nothing to figure out because there are no practical solutions that will resolve this.