A lot of us dream of cruising at an early age, but the truth is that most do not have the resources to do so. The cost of cruising, maintenance, slip fees, etc., with out any income coming in stops most sailors right in their tacks. Getting married and raising a family tends to get in the way as well.
That's why I think you see so many of, how did you say it, GEEZERS out cruising. Most wait until the kids are grown and have reached retirement age.
If you have the means and no ties, I say go for it. Why not.
I look forward to the day when the kids are grown and I am no longer working, untill than, I will continue with my wekend trips and my (2) week cruises twice a year. Happy cruising!