I took a similar 'vow' in my twenties not to get too involved with women and definitely not to get married. This was fine while I was without a partner, but despite having a policy of waiting for the girl to make the first move, once I got one partner I couldn't beat them off with a shitty stick. So, although unmarried, I was quite busy for some years. I'm no looker and no great stud, but even telling them all about the other women in my life wasn't enough to turn them away.
Eventually I got married and failed to have children, then divorced and married again at which point I became a father at 52. Now I have children of 4 and coming up 2 and yes, I don't get the stuff done I used to. Plus I'm probably too happy to pour my heart out in great music. But, hey, these kids are going to support me in my dotage, just as soon as they leave school and start work. Maybe then I'll write some gorgeously rhapsodic music to express my unutterable joy at still being around.
Anyone who tells you women take up all your time hasn't considered children.