Without exception, my male friends with kids have significantly reduced their time and energy spent on their jobs to focus more on their small children. They all say that their kids are the most rewarding part of their lives. Most have highly-paid professional jobs. I expect to do the same, at least for the early years, when I eventually have children.
This seems to be a huge shift from the previous generation. My father and most of his peers worked long hours and contributed little to childrearing.
I think you're still in the minority but it's a good thing. I'm devoted to my spouse and my kid. I'll drop anything for them. Some of the fathers I know feel the same but some smell like mine and he was a piece of crap. I fully support parenting being a team sport and in my opinion, that's how we're going to fix the modern family, by making it better than pretend version of The Good Old Days.
I don't know about your good old days, but I am just emulating my very religious, very conservative father, who, like me, made similar career choices to spend more time with his kids, as well as that of my grandfather's. Their good old days were pretty darn nice and I fully intend to recreate it for my children.
Reduced but not abandoned, that's the difference. My wife works part time hours since since the birth of our son, but she would never quit her job entirely and that dynamic will change substantially once he's old enough to start school.
This seems to be a huge shift from the previous generation. My father and most of his peers worked long hours and contributed little to childrearing.