Was your startup successful? Knowing that would help readers decide whether your advice is credible.
Beyond that, it depends on what you value in life. The commenter probably doesn't care about being the richest guy in the cemetery while someone else may be obsessed with keeping score. Not saying one way is better than another - to each his own.
Perhaps in the future, even succeeding, you'll look back to those younger days in which you put aside everything for your pet project and realise you lost the opportunity to have great experiences with your friends, boy/girlfriends, spouse, kids and/or family.
Remember, working passionately in what you love is great, but forgeting that you are not a working machine, and that you work to live, not the reverse, are perhaps more valuable advice for your future self than all the books on productivity in the world combined.
My point was that, as I've gotten older, I've found that my most meaningful experiences have come from seemingly random encounters with people. The startup world is full of interesting people, but they all are kind of the same in terms of their daily lives and motivations. I wish I had spent more time in my twenties connecting with people who care about things besides venture capital, IPOs and the latest technology stack.
To that end, I now go out of the way to stimulate more random encounters. I'd rather take a salsa dance class than go to a big data meetup.