There are exceptions to every rule, but it seems safe to conclude that those who wait until their 30s or early 40s to really get in gear with establishing a career and accumulating wealth end up quite a bit poorer in the end than those who start 10-15 years earlier. It makes intuitive sense, of course, but it's also been established via long-running experience by many people. Basically every single "life coach" out there will tell you getting rolling in your 20s is important if your goal is to own a home, 2 cars, kids, and build wealth for fairly early retirement. I think the generic advice people give these days is that it's fine to basically be in extended young adulthood through your 20s and 30s until you are nearly 40 while you "find yourself." I find that to be pretty bad advice for anyone who has a dream of building wealth and having a major, meaningful career. Those I know nearing 40 who are still considering their options for what they want to be later in life clearly missed the boat and are behind. Once they hit their 50s they will realize they are well behind their peers. This stuff tends to compound with age.
I might be what some would call a "high-strung" person, but when I see someone at age 38 saying "One day I would like to get married, own a home, have kids, and work in <x> field" I have to cringe. It's at least a decade late to be having these thoughts...