"The reason for the abyss at other grades (thank you for pointing this out) is because we train so many IMGs at Foundation and ST1-3 who then go home or move abroad."
That is utter utter rubbish. Your lack of understanding of the system for someone who purports to know it all is amazing. The issues are so in grained - we never trained enough doctors, ego have since the 1950s required IMGs to support the services.
The implementation of the EWTD and prior to that in the mid to late 1990s of reducing hours meant that a 1:3 rota now needed to be delivered by 8 doctors. WE are now on to 1:12 rotas, so even more doctors are required to deliver what the few used to. So the UK looked overseas to fill the gaps in the more senior junior posts( and yes they wee called junior then)
It then took a few years for the medical school numbers to increase and 5 years for them to come through and still the numbers did not match.
12000 into 13000 jobs means we still needed IMGS.
So if all the IMGS piss off back home which you and purple want to see happen - the UK would once again have a shortage of doctors and be going overseas to fill the gaps.
If you want to argue a cause -lear the history of that cause. The job that I started my SPR training i was a 1:4, I am now finishing off in the same job which is a 1:10 - where do you think those doctors have come from to fill those gaps in 7 years.