Blizzard: You will need an SSD to play World of Warcraft: Shadowlands
World of Warcraft was never a game with insane system requirements and this will not change with the release of the Shadowlands update. However, the part where Blizzard mentioned at least 100 GB of free space on an SSD — for both the list of minimum and recommended requirements — might darken the day of some players. The good part is that those running the beta on an old-school mechanical hard drive have nothing to complain about the game's behavior right now and Blizzard might adjust the list of requirements until the release of the game.
Compared to the system requirements for World of Warcraft: Battle for Azeroth, both the processors and video cards needed to run the game properly have been pushed up. In this moment, Blizzard claims that World of Warcraft: Shadowlands needs at least an Intel Core i5-3450 or AMD FX-8300 processor (minimum) and Intel Core i7-6700K or AMD Ryzen 7 2700X (recommended), NVIDIA GeForce GTX 760 or AMD Radeon RX 560 (minimum) and NVIDIA GeForce GTX 1080 or AMD Radeon RX Vega 64 with 8 GB VRAM. The Intel UHD 630 iGP is also supported. The amount of system memory needed is, basically, 8 GB (4 GB for minimum requirements, but 8 GB when using an integrated graphics solution and when talking about the recommended specs).
According to multiple user reports that were shared on the official forum, the game simply loads much faster when installed on an SSD, but should work just fine on a hard drive for those who have a bit of patience. Remains to see if Blizzard will change the list of minimum system requirements accordingly before the October 27 global launch of World of Warcraft: Shadowlands.