My 0,02€: Having become a dad late in life, I have plenty of perspective. When discussing our 3yo with my wife, I note that I've identified a couple of deficiencies in my own upbringing & school-age experiences that I don't want my kid to have to repeat. Just trying to leverage the benefit of experience.
Didn't have kids young, and man they're tiring, but in exchange for energy I can see what I want my kid doing and NOT doing. And really, it's mostly the NOT-doing stuff I'm worried about.
The kid will be into what they are -- it would be nice if they're into the same stuff as me, but it's fine if they aren't. But there are a bunch of situations I wish I didn't have to go through that I'd like to spare them from. Biggest one being a military brat and moving a lot, and never really being able to dive into a hobby or group.