Don't know if it's cheating cause I was part of the team that worked on it, but - Watch Dogs: Legion. I truly believe it should've become a pure PS5/XSX experience. PS4/X1 was leading to nothing but compromises to make the Play as Anyone system work.
Ambulances arriving to take wounded people? With our limit of, IIRC, 40 NPCs (and a couple more reserved already for law enforcement reinforcements), spawning new ones, which implies not only new NPCs with their schedules, memories, etc., but changing the schedule of existing ones in the vicinity and trying to fit everyone in the area, basically all that was too much, not to mention changing of memories/schedules of everyone in the vicinity, so in the end NPCs are just eternally waiting for an ambulance until you leave the area.
Blackout hack? Probably the most awesome hack in Watch Dogs.... same. Mass changing of schedules and memories due to blackout is not something that could be handled well on PS4/X1.
And even memories - I've mentioned those several times, but if I'm not mistaken we eventually had to cut down the amount of memories per NPC to 5? Which is just too small of an amount not only to make it feel like you're truly developing long-term relationships with NPCs, but also just in general to choose the appropriate reactions/lines.
Technically these are 'cuttable' features that the game/systems can live without, sure, but you cut one little thing, another one, another, another, streamline another, compromise here and compromise there, and now the collection of everything does not lead to the experience you'd necessarily find ideal.
That being said, I think the WDL team overall did an awesome job given all the circumstances, but also I think if we were allowed to just forego PS4/X1 (despite the original release date targeting end of 2019) and focus only on next gen, there's a lot in the game that would turn out quite different and far better.
