Back when I went into the vocational track in the UK at 18/19 it was 4 years doing day release to get to HNC level - that was specialist thermo fluids for the turbine/ aerospace industry - ironically all but one of us on the course was working for world leading RnD.

Now the same grade the equivalent of ASO (assistant scientific officer) is a degree entry Maggie Aderin-Pocock (one of the sky at night presenters) started out as a ASO at RAE post degree, and ASO is what Bob Howard was recruited as (Bob got screwed on that btw)

I have also heard it said the US has 4 year degrees as high school isn't hard enough.