E3 was only cool when it had some mystique about it because it was only available to the "industry" and the only way I got info about it was from magazines.
The second I started seeing livestreams of the show floor, it seemed like everything went to shit. I assume this is because they started wasting all their time and money on the spectacle instead of just showing off the games.
It can still be an entertaining trainwreck, of course. But even that seems to have gotten weaker in the past couple years with Game Awards replacing it.