The city could've been abandoned before it rose up or Vergil could've chosen to rise Temen-Ni-Gru in a desert the plot will still play out the same. The casualties in DMC3 didn't matter at all to the plot. DMC3 only alluded to people being murdered since you blood markings and Dante (in game) commenting on some of the demons dragging humans away. Well the plot of DMC5 actually demanded showing people being impaled and killed since it required human blood sacrifice. Whaaaaaaaat? Really? Dante cryed in dmc 3 for him, and also after he fight him in dmc 1 he was a bit spossed, but in dmc 5 want to kill him as soon as possible, strange Also dante say : you have some pretty big cocones for coming back? When they reunite vergil is not simply urizen but v too, so he maked many good action, but in the end its a bit weird. In dmc 5 urizen killed many people using the quliphot three but many other demon besides malphas are simply following theyre desidere to take the fruit before urizen, and V the human side of vergil helped people during the one month gap, and also helped Nero and dante destroyed cliphot lesser three.
Infact in vergil intro in dmc 3 and in the manga vergil himself is seeying fighting the same demon as dante. And actually the demon doesn't follow his order in dmc 3, beside the one you see going to vergil at the end of mission 2, the other simply are by themsefl protecting temen ni gru or other places. Yeah that s a bit weird but in the end I dmc 3 vergil was not the only responsabile but arkham too. Why not just have the game take place on an uninhabited island like in DMC1 at that point? But then they just end up not doing anything with it. They go through the trouble of showing civilians getting impaled in the prologue, soldiers getting butchered in Mission 1, and you can see the standing/kneeling corpses of people drained by the Qliphoth. But it does make question why would they focus on it so much if it wasn't going to be a major point of contention for any of the characters or outside of the prologue? Now this isn't a big problem for almost any player, people like Devil May Cry for it's combat.
(And I've already started to see jokes about how Dante is basically having playful banter with a multi-mass murderer and terrible father by the end.) And save for maybe 1 or 2 parts of the shorter cut-scenes, no character is really angry at him about it and Vergil isn't really sorry by the end.
DMC 5 VERGIL FULL
Spoilers obviously: Similar to what happened in DMC3, in DMC5 Vergil is directly responsible for destroying a city(ies) full of people.