Peter Capaldi is the 12th Doctor, but Steven Moffat and BBC casting another white guy didn’t sit well with many fans and critics. The announcement special drumming up publicity didn't help counter those misgivings, nor did Moffat’s flippantly inaccurate quip that he’d “like to see a man play the Queen,” since that already happened in Orlando 20 years ago.
Author and devout Whovian Neil Gaiman has been far more tactful about answering questions surrounding Capaldi’s casting on Doctor Who, as well as the push for the ever-changing time-traveler to be played by a woman or an actor of color. Responding to various questions about it on his Tumblr, Gaiman gave a well-reasoned response to why he doesn’t think it’s quite the right moment for a woman to play the Doctor, but he did say the show came pretty close to having the Doctor be non-white:
“I thought I’d said that I was disappointed that it didn’t happen this time, and that there are some amazing actors out there. I was rather disappointed that Paterson Joseph didn’t get it last time, although I’ve loved Matt [Smith]’s Eleven. And yes, I have no doubt there will be. (I know one black actor who was already offered the part of the Doctor, and who turned it down.)”
Speculation over whether the unnamed actor (whom Gaiman won't name, since he was told in confidence) was rumored contenders like Idris Elba, Chiwetel Ejiofor, David Harewood, or someone younger like Daniel Kaluuya can now commence.
Gaiman also offers plenty of other insights into why Capaldi was ultimately a logical choice to follow Matt Smith as the next regeneration of the Doctor. But perhaps knowing that producers at least considered this other direction takes a bit of the sting out of the controversy.