The analogy with the medical profession is compelling.
I've just passed out of medical school and want a Ferrari and a big house. I should be allowed to be a senior registar
But entirely inappropriate - nobody gets a "shot" at being a consultant, let alone by waiting in turn. The best doctors go up the rungs far faster, and if an open position exists, can apply, and if they are the best, they get the job.
There are a fair number of consultants who are only 30. Some never make it, nor are interested. It is a meritocracy and not based upon seniority, yet remains entirely safe.