The metaphor is broken. The snowball grows passively over time naturally, but being a founder requires you to actively create value in your startup. Snow doesn't choose to stick to your ball based on PMF, and the entire piece romanticizes grinding without once mentioning customers, revenue, or whether you're solving a real problem people will pay for.

I think it's dangerous sentiment to say if you create a snowball (startup) and just keep pushing it forever it is guaranteed to grow to something large. Some might say "duh, of course", but I still think a lot of people don't understand this.