> * Run on hardware an order of magnitude more powerful than was available to the original WoW server devs, meaning that much simpler solutions with far less sharding / IPC / configuration can still scale sufficiently well

well the hardware was never a problem, but the user base.

you can basically run a 100 people reverse engineed wow server on basically a server with 2gb-4gb memory and a non virtualized cpu (a older gen one, dual core probably enough) and you would more run into networking limits than in actually performance issues.

the problem with wow classic/burning crusade/wrath of the lich king, was mostly the overwhelming people, servers took way more than 100 people, and the biggest problem was logging them in, if there was a prime day, all sharded servers could login too many people which overloaded login servers quite regulary.

> Run on hardware an order of magnitude more powerful than was available to the original WoW server devs

Back in 2012 Blizzard sold the original servers off for charity so we actually know what they used (HP p-class blades).

https://www.geek.com/games/blizzard-is-selling-old-world-of-...

The other thing that's startling to me is that not that long ago pretty much all game servers were hosted by people other than the publisher of the game. I don't think there ever was a Valve hosted CS 1.6 server and it's still true that the vast majority of TF2 servers are community run. I think the same is still true for Minecraft. That worked really well.