Culturally competent care is important. We must all learn how to provide care which takes culture into account.
But regulation is not the answer.
First, the majority of physicians provide competent care
Second, culture is not 'white.' Most people take me as white. I usually decline to fill in that section of employment or government forms. White does not describe me in any way. I was born on the Asian continent to a North African family that can can trace its roots to the 5th century invasion of Greeks and Romans which created more Christian martyrs than pagan rule. My mother is European. Most people who feel that 'white people' need to be educated, trained or otherwise regulated are counter-racist and do not understand culture.
My Latina wife would probably be the first to recognize that in the Latino community, culturally competent care means getting the Argentinian to be nice to the Honduran, or the Columbian not to look down on the Peruvian (I am deliberately avoiding the countries that have true issues of intra-Latino prejudice.)
The legislators in the Kaiser article mean well, but miss the mark by a mile. The most important part of culturally competent care is placing culture right at the center of personal communication skills. No patient can be taken care of properly without some consideration of the personal, family, social, cultural, and ethnic experiences which shape their interaction with health care.