While you're correct, there's generally a correlation with something that's not only existed for that long, but IN USE for that long. I think that's the bigger selling point. Maybe I only get this idea from going through all comments on HN, I see your comment is from 8 hours ago, and I don't know what comments existed at the time you commented. I apologize if you didn't have much context when making this comment.
The point is to communicate a large amount of personal investment - love, sweat, and tears. As opposed to someone who scraped together some side project in a weekend and hasn’t yet faced the demon horde of edge cases.