I had never thought about it in those terms; I suppose that could certainly have been the reason in some cases, or a contributing reason.
But it's also true that Americans in general often just don't, or didn't, know how to pronounce German vowel combinations like EI. There's so much variation, and so much of it seems just random, that I'm often unsure if a particular person, or family, pronounces it Stien or Stein, even if they're famous, like Leonard Bernstein, or infamous, like Harvey Weinstein. Who apparently is called 'wine steen,' for whatever reason, even though I can't see how someone would have ever looked at those two parts with the same spelling and come up with two different pronunciations.
Others like James Levine I assume might have been originally spelled and pronounced as in French, but in English it seems to sound like the English word 'vine.'