Well, that's surprising, and a little disappointing.
The main thing this tells me is they're clearly shifting all main, 1st party resources towards PS5 and they're inclined to let 3rd parties take over the PS4.
Another thing this tells me is whatever they have in development is not far along enough for them to reveal as early as E3 and the content they do have to show is mostly content we've already seen in past E3s (Death Stranding, Last of Us II, etc.) so there presentation would probably be disappointing if that were the case.
Or, and this is probably most likely, between PSX, TGS, and other press announcements, Sony doesn't see E3 as a priority anymore.
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