Demonic robots fit Castlevania more than some of the enemies in SOTN on the Saturn. *looks at enemies in the Underground Garden*
Seriously, though, just because it's in the modern setting does not make it a bad game. Sounds like people are criticizing the game for not appealing to fans of the previous Castlevania games and for it being something that it isn't. Even if it is similar to God of War, (I haven't played GoW, for various reasons) a good reviewer would review the game based off of it's own merits, not what it's based off of or took inspiration from. As for the whole "game holds your hand" deal, they are letting you turn the tips off this time, something I am personally doing myself.
At this point, the whole "modern city, it's not Castlevania!" complaint is starting to sound like the hate that Metal Gear Rising gets due to it being a hack-n'-slash compared to previous Metal Gear outings. Castlevania Lords of Shadow is not the same as the Castlevania that people saw in 1997. Mercurysteam's take on Castlevania is it's own, separate thing from Konami and IGA's takes on Castlevania. They should have reviewed it as such. I know that's how I'd review it.
I was going to watch the video, but I was busy with some stuff, and the comments seem to sum up what the reviewers are saying fairly well.