Diablo 2 producers and former Blizzard employee Mark Kern said the reveal of Diablo Immortal is an example of Blizzard "not understanding gamers anymore".
Blizzard has not yet announced if Diablo Immortal will be a free or a paid title, though Blizzard developing the title with free-to-play veteran NetEase might offer a clue.
Despite asking fans to reel in their expectations for Diablo-related news at BlizzCon 2018, it turns out the company had plans to tease the development of Diablo 4 anyway. Whether or not this video was planned to be shown at BlizzCon is in question, but Blizzard said in a statement that it "didn't pull any announcements from BlizzCon this year or have plans for other announcements".
If Blizzard had shared a teaser for Diablo 4 at BlizzCon, even a wafer-thin one like a GIF of a flaming "4", Diablo Immortal's reception may have been more positive. The fan backlash against the game was strong enough that Activision Blizzard's stock price was impacted. The game's cinematic and gameplay trailers were besieged with dislikes on YouTube, and the Diablo subreddit is awash with high-upvote posts calling Immortal "a slap in the face" and accusing Blizzard of being "out of touch with their fans".
It seems that some folks at Blizzard wanted to clear things up a little, as Kotaku received tips from numerous sources that not only confirm Diablo 4 is in development, but that an announcement video featuring the publisher's co-founder, Allen Adham, has been made. We've heard from the hardcore Diablo fans that feel spurned, the ex-Blizzard producer that thinks Blizzard dug its own grave, and the developers themselves that have continually stressed that multiple Diablo projects are in the works.
"Diablo fans reacted as though, after a 12-year relationship, Blizzard had taken them out to a candlelit dinner and a long walk upon a moonlit beach, then gifted them a pearl necklace". Last Friday, Diablo III also came to the Nintendo Switch. One of them is the game that fans are waiting for, and it was almost announced last week.