It sounds like Blizzard will be putting out a new Diablo game soon. On their careers page, Blizzard seems to have inadvertently let slip that a new Diablo game is under development. Diablo 3 came out in 2011, with Reaper of Souls coming out in 2014- it’s been long enough since either way, so we’re due for a new one regardless.
Now, in case you think this might indicate, say, a Switch port- nope, this is explicitly a new game, because they are hiring a “dungeon artist”. A port already has all the dungeons made- this is new content being developed. Which either implies a new expansion, or a new game altogether.
This is excellent news, of course- and hopefully, Diablo 4 will be better at launch than Diablo 3 was. Of course, Diablo 3 ended up getting a hell of a turnaround, and is now arguably the best game in the series- but hopefully, Diablo 4 won’t have to go through the same protracted cycle.