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Here's the primary question, does going cross gen change the scale or how the game functions? If the answer is no, then it doesn't really matter.
9th gen games on average are going to be a lot like 8th gen games with much better visuals. Its very likely these games were always planned for PS4 or the scale of the games wasn't beyond PS4 capabilities.
Sony probably lied about focusing solely on next gen because they weren't entirely committed or sure PS4 support was continuing. So its been a good laugh for people who always felt cross gen support makes sense for some projects.
Recently Completed:
River City: Rival Showdown for 3DS (3/5) - River City: Tokyo Rumble for 3DS (4/5) - Zelda: BotW for Wii U (5/5) - Zelda: BotW for Switch (5/5) - Zelda: Link's Awakening for Switch (4/5) - Rage 2 for X1X (4/5) - Rage for 360 (3/5) - Streets of Rage 4 for X1/PC (4/5) - Gears 5 for X1X (5/5) - Mortal Kombat 11 for X1X (5/5) - Doom 64 for N64 (emulator) (3/5) - Crackdown 3 for X1S/X1X (4/5) - Infinity Blade III - for iPad 4 (3/5) - Infinity Blade II - for iPad 4 (4/5) - Infinity Blade - for iPad 4 (4/5) - Wolfenstein: The Old Blood for X1 (3/5) - Assassin's Creed: Origins for X1 (3/5) - Uncharted: Lost Legacy for PS4 (4/5) - EA UFC 3 for X1 (4/5) - Doom for X1 (4/5) - Titanfall 2 for X1 (4/5) - Super Mario 3D World for Wii U (4/5) - South Park: The Stick of Truth for X1 BC (4/5) - Call of Duty: WWII for X1 (4/5) -Wolfenstein II for X1 - (4/5) - Dead or Alive: Dimensions for 3DS (4/5) - Marvel vs Capcom: Infinite for X1 (3/5) - Halo Wars 2 for X1/PC (4/5) - Halo Wars: DE for X1 (4/5) - Tekken 7 for X1 (4/5) - Injustice 2 for X1 (4/5) - Yakuza 5 for PS3 (3/5) - Battlefield 1 (Campaign) for X1 (3/5) - Assassin's Creed: Syndicate for X1 (4/5) - Call of Duty: Infinite Warfare for X1 (4/5) - Call of Duty: MW Remastered for X1 (4/5) - Donkey Kong Country Returns for 3DS (4/5) - Forza Horizon 3 for X1 (5/5)
