It should be ludicrous, however, unspokenly, it is not.
It is simply a matter of logic. Speaking
on average, to expect that IMGs would be "better" than AMGs is "ludicrous", a PC statement, for the following reasons:
1-USA spends in training of its MDs more than any other country in the world
2-US medicine attracts the best of best native Americans (it is not the case in many other countries)
3-AMGs have natural advantages in spoken and written language + customs + habits + looks + built in relationships, etc.
To be otherwise would be a serious indictment to US education system.
This does not mean that an AMG would be a better doctor in any foreign country for obvious reasons. Do you get it?
US is the most welcoming and generous nation towards the foreigners, in the earth, bar none. Many foreigners can not be what they are even in their homeland.
The main reason there are so many IMGs in the USA is because, for decades, the demand had overwhelmed the supply, so much so that for close to 2 decades IMGs where given the most preferential visa status (i.e., no waiting period of any length) to come into USA.
Your mention of "most valued and respected" IMGs is not untrue, but a stale cliche.