Why wouldn't the trend to become a doctor increase in the first place? If more people are going to be able to actually see a doctor instead of an ER nurse, what better incentive than the ol' "supply and demand" rule here?
Easy - when the government controls prices and limit's one's earning ability, one has an incentive to seek a more lucrative career. An increasing number of doctors are already refusing to see Medicare patients because they lose money with the fee structure. Once everyone is under a government fee structure, we'll see a shrinking supply of doctors.
Unless, of course (and this is a possibility), the government decides to increase the supply of doctors by subsidizing education for ill-qualified students who will make the DMV clerk equivalent of surgeons.
You constantly display a complete and utter ignorance of economics. Please, get a decent book (i.e., something by Hayek or Friedman) and read.