They are but sadly this is what sells consoles. I think 2 years maximum is a sweet spot to generate new hype.
Year 1 E3 - show a trailer and maybe some game play
Year 2 E3 - playable on floor
Release at Christmas
If studios planned their release schedules better we wouldn't need long announcements.
The problem is they release all their aces in one hit then we are stuck with droughts, so people want to know what is coming in the future.