I wonder same at times, it's much like real world economy where rich gets richer and poor stays poorer.
Many people here have expressed the preference to merit lower ranks. They're saying the lower ranks don't create good enough posts. If they did then they'd be flying up the charts.
The small amount of shit hot posters who arrive out of nowhere reach ludicrous heights in no time at all. That had nothing to do with privilege or nepotism. What they had was recognised by others and awarded.