Hrant you are a complete jerk.
Objectively the above does not mean that a small number of designers are getting all the money all the time, it means that the "best selling" designers are making more in some years, and less in others - it does not mean that there is a small hub of designers "making a living" (your mythical 10), it means that there are many, whose income may fluctuate over a period.
If you look at any best selling chart the work of Frutiger is always there, you'll note what professor Spiekermann wrote about the royalties Frutiger gets. ie even having a best seller may not do you any good.
Or maybe you meant something else, you did not explaining either way. Usual m.o.