Everyone has time sinks. Just about everyone over the age of 22 works at least 8 hours. 9-5 are lighter hours than anyone I know excluding those who are shift workers. I don't know anyone with a white-collar job that gets off before 6, and many start before 8. I work some of the lightest hours of people I know at 9-6:30. We all find time to network.
New grads/young professionals track me down regularly asking for "career advice" (a job). People my age/older email me about potential job opportunities. Coffee with either of them is pretty effortless given that both of them will typically come to you. Meetups[0] after work usually start at 7. I probably get to about 3 or 4 a month which is plenty to build a superficial network outside of my immediate friends and family. I don't have children. Even if I did though, trading 2 nights a month my significant other for personal/career networking isn't all that unreasonable. A friend of mine runs a meetup and he has 3 kids.
I sleep 7 hours, I'm at work/commuting 11 hours. That leaves me with 30 hours on weekdays to divide however I please (obviously there are other basic sunk costs like basic hygiene and eating). I've found that once I quantify the time I have in life, it's a lot easier to notice when it's available and be productive with it. I'm really not even one of those super motivated people. I just like to be conscientious of my free time.
