Hahaha, I watched Angel before I had ever watched Buffy. It was introduced to me by a friend... who was a guy. He always said Angel was for the guys and Buffy for the girls... aaand now I'm pretty sure I just insulted myself. : erm :
I'm not sure I agree completely with your friend's opinion on the matter, but two scenes come to mind for me when I think about this. The first is in BtVS when Xander in s6(or was it s5?) is talking about something pretty much guy oriented and all the girls look puzzled, he goes and say 'I really need to have some guy friends', lol.
And then the other scene is in Angel season 5 when they're under an illusion and Angel explains to them his plan and they all lift their hands. It reminds you that both Cordy and Fred are dead, the team pretty much lacking a feminine side(I don't count Illyria because after all she isn't a human).
So if your friend mean't there's more girls on BtVS and more guys on AtS, then i'd agree.