Exactly, I do not count, 'Hey we've made it five years now, but can hardly break even and have no clear vision of where to go from here' as 'alive'. In fact, by that time, the investors have probably written them off and will be trying to figure out if they can salvage some talent from it before their runway ends. In the end, YC or not, less than 10% of these guys will become real companies. It's just statistics. YC may get you the seven figure round, but if you keep your, 'product', or 'feature' as such for a few years, you're dead.

Edit: Not trying to discredit what these start ups have done so far, it's very hard getting to that point alone.