The problem is that the graduate academic system doesn't necessarily choose for the best astronomers. The most dedicated? Sure. Those willing to sacrifice family lives, the ability to start saving for retirement, and a peace of mind that they have a future in that profession? Yeah. But that doesn't mean the smartest or most talented. It means the smartest and most talented of the subset of people willing to lead such an existence.
The idea that the system has to be as masochistic as it is, with people now doing post-docs well into their 30's, having no real financial stability through all of that, and being expected to make huge sacrifices in personal relationships, all for a magical goal of tenure that well over half of those people will never achieve, is flawed. The rigid system of academic levels is flawed. Advancement and reward should be based on research done, quality of publications, and recommendations, period. The stress put on students for quals and dissertations is a huge waste. It's an out-dated hazing ritual. It's a source of cheap labor. And it kills the love that many people, some of them brilliant people, have for science.
I agree that there are always going to be a limited number of positions for astronomers, or for scientists in general. But I damn well don't agree that the current system is the best, most efficient system. I think it loses a lot of great talent, I think that the establishment is not recognizing that it's becoming more and more stressful, and I think it's a real shame that we're stuck in a system that was developed a long time ago for a very different world, just because it's always been that way.