In most countries that do this training is longer which that total training time is only 1-2 years shorter.

So you’re doing a few things.

1. Moving more training from cheaper colleges to more expensive medical schools.

2. Moving the filter from undergrad to medical school

3. There is no national curriculum in US high schools, so essentially the first 2 years is getting everyone on the same footing. Removing this without changing high school, puts students at poor high schools at an even greater disadvantage.