Not a huge loss really for us. E3 is huge mass of information already even without Sony and with the PS5 on the way (who cares right - this is PC gamer) having it on full blast at a later conference would be better.
E3 has been on the decline for awhile now. The last one I was at was about 7 years ago. I previously worked for Activision, EA and Square Enix between 2000-2012 so I've been to quite a few. It has changed dramatically from what I hear.