An Interesting Opinion Video by non gaming media Engadget which I also agree 

Video conclusion

1.Sony Days of Play already happened before E3, which are a lot of price discount and console bundle and special console design

2.Sony State of Play already making a lot of buzz far before E3

3. Many Third party games already directly and indirectly promotes Sony

4.Many Sony partner (AMD for Example) already also promote PS5

5. PS5 announcement already stealing some hype and dominate the buzz and words among casual gamers and mainstream media 

6. Even Microsoft announcement is just indirectly announcing PS5

7. Final Fantasy 7 Remake steal  a lot of attention and create big Hype, and is coming exclusively for PS4

Sony is officially a shinobi and Ninja and has mastered the art of war without anyone notice