A number of studies here in Canada have found that resumes are more likely to get a call-back if the person's name is typically Anglo-Saxon as opposed to pretty much anything else. I think the effect has been shown in the USA too.
Employers are probably biased towards hiring a "John Watson" over a "John Adeyemi" or even a "John Kaminski", all other things being equal. So people change their names. It's pretty common. I doubt show business is any different.
Our sales guys have african-sounding names; after taking alter-egos of western names, their response rate tripled up to the normalized comparison of other employees with western names.
Employers are probably biased towards hiring a "John Watson" over a "John Adeyemi" or even a "John Kaminski", all other things being equal. So people change their names. It's pretty common. I doubt show business is any different.