The problem is that doesn't automatically equate to getting better and it definitely is NOT heathier lets face it... who can deny Flex Wheeler looked his best at around 225lbs?
Flex and just about everyone else looked their best when they weren't at their heaviest. I think weight restriction is something the IFBB should consider. Especially since the extra weight is usually carried in the midsection anyway. Competitors would be more focused on refinement and small waists rather than mass at all costs no matter how it's carried. Diuretics testing would have to be heavily enforced though, since conditioning would be a big factor.
We also need to limit the length possible in the long jump, and the lowest score in golf. How about capping the most home runs in a baseball season? Definitely.
Track athletes, golfers, and baseball players all have restrictions in their sport. They have to use regulation equipment (track shoes, regulation golf balls, wooden bats), and bodybuilding basically has no rules. Setting up rules for the sport helps legitimize it.