>>149442495 (OP)I believe the actual policy is "non-white characters shouldn't be voiced by white people". Many white characters are voiced by POCs, and some POC characters are voiced by different POCs.
The logic is that the voice acting industry is still mostly dominated by white people, which is admittedly true, so roles for non-white characters should go to non-white people so that more people can have jobs. Not everyone in the industry agrees, and as time goes on and the talent pool and the roles become more diverse and the old white voice actors start retiring, things might change once the policy is no longer seen as "necessary".
Anime dubs seem to be the exception to this trend, most likely because the vast majority of Anime characters are Japanese, and expecting every single role to be done by Asian VAs is just unrealistic.