I must say that E3 hype is going to be missed, but if Sony announce this time (not like last year) their own event, everything will be forgotten, because Sony doesn't need E3 at all. PS4 was announced at their own event and was hyped as hell. With PS5 will happen the same.
As for E3....well, obviously, seeing what happened last year, E3 won't be dead of course, but i must say that last year already saw a decline in hype, not only because of Sony withdrawing, but because of lot of leaks and lack of amount of new games. Besides that, i think that most people, when Sony announced they weren't going to go to E3 2019, still thought they were going to go all in in E3 2020 instead. Now, this looks more like Sony is done with E3....for good. E3 can survive a year without Sony...., but consecutively years without them??? What if this forces EA, Ubisoft, Square Enix...., or even Nintendo to do the same???. That's the risk E3 is taking right now.
I still expect E3 2020 to be decent, thanks to Microsoft and Nintendo still doing things there...., but come on, an E3 without Sony is a serious blow for the show.