If Muslim parents refuse to accept their son's gf only because she's white, aren't they committing a sin?

I remember u. Well idk if u said whether or not his parents know u two r dating yet, so maybe use that at ur advantage by just making him say he know sthis Muslim girl (that he never dated) and he would like to marry her. Yes it is a sin for them to not accept u despite being Muslim just bc ur white. Im only a tenager but I know this stuff kinda bc my uncle(who isnt religius at all) who was raised and born here in the US married a catholic lady. My family didn't really seem to care, but we see less and less of my uncle bc we dont really mix in well with him and his wife(they're just more Americanized than us). U really can't tell what ur bf parents will do tho bc I'm Pakistani and many paki ppl care more for culture than religion(not me!), and when he says his parents r strict most likley they're more strict about culture than religion. They're probably scared u and ur family won't mingle well with him and his family bc families a big deal. So no one will know really until he tells them something. Good luck.