I agree with Clunk. I believe if bodybuilding simply stayed on a course in which competitors looked heavily muscled and symmetrical, but did not have to go to the ridiculous extremes of both size and leanness, then bodybuilding would have gotten more and more popular and there would be far more competitors. Because the average salary of IFBB pros is $0.00 per year, it's not a surprise that there are not as much competitors as some organization head is looking for.
Hardly anyone with a job or a normal life can afford to go to extremes (financially, mentally or socially) mentioned, and I believe if there are still high judging standards, but with more manageable criteria. Many people with lives can build lean and heavily muscled physiques and actually participate for fun and satisfaction and no money. But don't expect an appreciable amount of people to risk their health, jobs, social status, and so on for payments adding up to $0.00 per year. Then it's not fun.