Racism by omission has been an issue with D&D and SF&F in general since day one.  Where the 5e PHB stood proudly apart from the trends of the past, the 5e DMG doubled down and dug in. The interior of the book is richly illustrated, with magical items, fantastic landscapes and maps. To examine the art this time, I used a simpler system. I didn’t count any image that didn’t include a playable race. Of the remaining images, 43 were of individuals or teams with no POC of any sort. Ten were either too ambiguously coloured or the perspective prevented identifying the ethnicity of the characters in it. Four contained identifiable POC, and one appeared to have a POC and an Asiatic elf. So, counting the last one (it was almost an ambiguous selection) that’s a ratio of roughly 1:5 for illustrations including POC or of POC alone versus images without them. This is literally undoing the amazing level of inclusiveness that the PHB laid out.
Function and game play wise, things are back to normal with this DMG. It’s well stocked with familiar and new magical items, and contains the full rule set for doing what you need to do to let your players try to do what they want to. It also has a great section on magical item creation, and an equally good section on altering or creating monsters. The part on the planes is fantastic, and far more detailed than previous DMGs have provided. Like the PHB, the DMG also tries to provide information to play on any one of several established game setting worlds.
The latter point is one that I can see becoming an issue in future, since it’s dependent on the players and DMs already being familiar with the game settings mentioned. It’s a nice touch, but I’m wondering now whether its going to weaken future core products. The book is also still slim on details beyond factions for the alleged new base setting, Forgotten Realms. I’m hoping that the Realms will get their own set of books again, since the amount of detail and background that exists for that world is really past the scope of the base books.
My overall impression of the new core book set is positive. I like how the rules look on paper, and the feel is good too. The game “feels” like Dungeons and Dragons. The PHB did the most to win me over though, since it went out of its way to present a diverse, interesting, and dynamic game to me. There are still some issues with racism from years past in existence, but the game as a whole has made a large leap forward. Hopefully this trend will continue and the game will continue to become more inclusive and more nuanced.