E3 is an outdated showcase. In an era of livestreaming and news directly from the publishers, E3 is just the unwanted middle man now.
While this may be true as much as I love my E3 time watching all the streams, direct publisher news will never replace the joy of E3 seasons for me because there wouldn't be multiple live-streams from folks like Giant Bomb and Gamespot actually having to come together and report things as they happen.
If everyone goes Nintendo Direct across different times of the year it will just be news to watch with maybe reaction or discussion videos posted after and the whole "live" excitement and anticipation will be gone. It's a bit similar to watching a football (soccer) game recorded after it happened. Even if you didn't spoil yourself on the outcome yet there's just something missing from the experience. Actually writing this, a better example with football would be the Worldcup. Football happens mostly all year round but even I as not even a football fan enjoy when the Worldcup happens as that's a time where there's just a certain excitement in the air, the media and even people who don't watch football come together and celebrate and discuss.
And to clarify, I'm not missing the actual live-shows with an audience, it's fine if the announcements themselves are pre-recorded, but I rather have one condensed time-frame or week within the year were a whole slew of publishers and developers come together and everyone anticipates, guesses and predicts news live.