American helicopters are high... Eurocopters are low
Not even close, it is entirely the choice of the operator
It is simply the old and the new, originally all a/c were low, all new a/c ( with the exception of the military) are high.
CHC (Okanagan) made the choice years ago to convert all (US and French built) new a/c coming online to the old low style, only after the introduction of the 76 C+ did they finally decide to go modern and have all new a/c delivered with high. Unfortunately now for crews on 76's (A,A+, A++ and C+,C++) means carrying 2 mics for the Bose. A bit of a pain in the a$$.