Three things:
1. You are confusing P(A|B) with P(B|A).
2. Even if it were true, a lack of bias against a few minority groups would not invalidate the statement that there is bias against other minority groups.
3. You are conflating a very wide and disparate set of ethnic groups in a way that is very misleading (and mathematically similar to Gerrymandering[0]). If we were to break those very broad categories further, we would see that many groups that qualify as "East and South Asian" are still themselves under-represented.