If I were a younger doctor 1) I wouldn't be able to post anonymously because the GMC disapproves* and 2) I would be worrying that with moves such as self-declarations afoot and the diminishing number of ppls, the supply of work might dry up.
Dabbling in aviation medicine doesn't look like an attractive option; the amount of work required not just to qualify as an AME but also to stay on the register (having one's premises inspected etc...) seems quite significant. You'd have to be doing a lot of work per year to make it worthwhile.
1/100 PPLs will die flying, often taking other people with them. Medical issues _are_ implicated fairly frequently, so I would anticipate an unpleasant degree of scrutiny from time to time.
This is just my impression from reading the requirements. If any AMEs would like to tell me otherwise, I'd be interested. However I suspect that we'll move towards there being a smaller number of more active AMEs - which may be no bad thing.
* This was very controversial and felt by many doctors to be an unwarranted intrusion on one's private life.