The two sources of the rumor, as Kotaku reported,stated that at the end of the Diablo Immortal video, the original plan was to have a short teaser for Diablo 4 (kind of like what Bethesda did for The Elder Scrolls VI at E3) to assure fans that a new proper Diablo was on the way. But then it was pulled, for, as I explained above, no discernable reason.
Now, if it were just a rumor, that would be one thing: that’s a pretty petty rumor to start just because you don’t like admitting Blizzard can be at fault for something. But in an unusual move, Blizzard itself actually stepped forward and commented on the rumor, making it perfectly clear that, no, there was never any intention to make such a teaser. Ya’ll just need to shut up and deal with their probably-crappy mobile game.
"We generally don’t comment on rumors or speculation, but we can say that we didn’t pull any announcements from BlizzCon this year or have plans for other announcements. We do continue to have different teams working on multiple unannounced Diablo projects, and we look forward to announcing when the time is right."
So there’s still a spot of hope for Diablo fans, but then, the idea that Diablo Immortal was supposed to “replace” Diablo 4 was always silly: it’s a cash grab. And there’s no way Blizzard is going to leave money on the table and not also make Diablo 4.
But, you know how fans are.