LiquidSolid
Member
It's because those two don't really have giant announcements
Last year was obviously pretty weak (Sony didn't even have a Euro conference) but that doesn't mean they haven't had big announcements at them. Yakuza 6, Yakuza Kiwami, Nioh, Kingdom Hearts 2.8, Bloodborne: The Old Hunters and Gravity Rush 2 were announced at TGS 2015. While Gran Turismo Sport, Driveclub Bikes and Detroit: Become Human were announced at Sony's PGW 2015 conference. If anything, PSX has typically been much weaker than either of those shows.