This has basically nothing to do with the game, but hey, it's not like there is much news on that front anyway...
This means all the larger dinos died, which made it possible for mammals to take over the now open niche of larger land animals. It's unlikely that mammals would have been able to do this otherwise, so no large primates aka humans.
Only animals that could hide in the earth/caves or in water survived the Chicxulub impact event, because all around the globe temperatures rose enough to set wood on fire from all the small particles reentering the atmosphere. And even if some larger land animals survived, they couldn't find enough food in the following impact winter.Sure we would. It's not like they all died. If they did, the fossil record would be broken with an entirely new evolutionary population. A mess of them became birds.
This means all the larger dinos died, which made it possible for mammals to take over the now open niche of larger land animals. It's unlikely that mammals would have been able to do this otherwise, so no large primates aka humans.