The majority of the young people in Russia are genocidal imperialists. Support for extermination of other countries is of course higher in the older generations, but that doesn’t change the fact that a solid majority of young (e.g. 18 to 29) are genocidal imperialists.
I understand that it might be reassuring to repeat platitudes like “young people of russia are against the war”, but this is clearly not true.
Even the framing is suspect. What do you mean by “the war”; the full-scale invasion? In Ukraine, the war started in 2014 with annexation of Crimea and russian invasion of Donbas.