I've spoken about this before, I won't dismiss that could be part of it. But VA culture in general and how the Japanese approach it is very different to the west, we have some good VAs in the west but they are very few and far between as opposed to being everywhere in Japan, mainly because most japanese VAs also have careers in acting and music, aside from the fact Anime is almost everything in Japan, it's a pretty lucrative profession unlike here, where it's still fine, but not nearly as great.
So the skill in even some of our best VAs is almost never quite as natural and fitting sounding as the Japanese equivalent, that's just how it is, there are exceptions of course, but still.
For example, even though David Hayter wasn't great by the time he did Peace Walker, in MGS2 and mainly also 3, he pulled off Snake so well and even made fight noises and dumb things like that sound just as cool and natural as Japanese stuff, and not like some person trying to imitate their favorite character (Which is what most dub sounds like, even when it's decent)