For what it's worth, that may be because it reads less as advice and more as self-righteous sneering.
My mom, a single mother, started her own business while she raised me. The result was a higher standard of living than I ever could have enjoyed had she played it safe and stayed yoked to a crappy job that made her miserable. I also got to spend more time with her, since she was her own boss and could decide that, yeah, her son is welcome at work and can hang out there quietly instead of being in daycare forever.
To the author, I say hat's off to you. You bit off a lot to chew but keep at it and you'll have a better relationship with your child than if your time was not more under your control. Definitely a better deal than if you stayed at Goldman Sachs.
The guy who got my mom pregnant didn't stick around, didn't cut the cord, and sure as hell didn't pen a blog post about how excited he was starting a business and raising me, too. (edit: And, let's be clear, guy was a dirtbag so this is entirely the best outcome) So, speaking from experience, Antonio is all right with me.
Trying to do both now. Babies and startups aren't unrelated though actually. Oh, I feel another blog post coming on...