Here's my 2 cents:
I'm here at BlizzCon and I was in the room at the mythic stage during the opening ceremony. IMO the big problem is that they ended with Diablo immortal. I actually think the game looks decent and don't have any issue with it existing. But its placement in the show was super odd. If they had just placed it somewhere in the middle, it would have been more appropriate for the weight it carries. IMO they should have ended with WarCraft 3 Reforged or Ashe in Overwatch. None of it is ideal BIG stuff for ending the opening ceremony with, but it would have been a better fit for that slot in the show IMO.
Next thing, i played the demo twice. First time I played solo as a wizard, second time as a barb and with 3 of my friends. I actually like the game. It plays well, and in some ways it actually looks prettier than D3. (Which I noticed because I've been playing D3 on my Switch.) what we got to play was pretty short and simple, but I can see the potential.
The fact that they didn't even say 2019 for it is worrying though. If the game doesn't come out next year, phones are going to outpace them and the game will be built for 2+ year old tech by the time it comes out.
The whole thing is a mixed bag but at the end of the day I think it boils down to 3 things:
1. When it comes out, it should be a fun mobile game.
2. We know Diablo 4 is in the works. Once they're ready to show it off, they will. I too wish it was now but ¯\_(ツ)_/¯.
3. And finally, I think the core issue here is that they put this in the wrong part of the show. People would still be mad, but if it wasn't a "conclusion", the conversation would be different.
