“History is always white washed. How do we manage to have a diverse cast despite that? The way that we did it was … [to just] say that you will see people of different colors there. In fact, there were. People all didn’t arrive in the twinkle of an eye.”
–showrunner Steven Moffatthen they fired the first black companion because why not
That’s an unconfirmed rumor, though I will point out she is not the first black companion. It’s highly likely she will leave after this year, but there’s no evidence to even suggest her contract spanned more than a year in the first place. Her leaving is sadly just likely because of the changeover in staff for the show, with the other lead and the showrunner both leaving at the end of this year, most prominently. Firing doesn’t really come into it.
I very much would like her to stay, but there’s solid production reasons for her not to. If she is leaving, though, I hope whoever’s next isn’t white.
Bill isn’t the first black companion. Martha was.
And as illustrated by her continued presence in Torchwood and Who series 4, she wasn’t really fired either.
Hell, if you want to get technical with the definition of ‘companion’, Mickey was.
(The source of the rumour about Pearl Mackie being fired is The Sun, which is the UK equivalent of Fox News essentially, and has a long history about lying about POC/LBGT people/anyone marginalized they can get their dirty little hands on. They also claimed Freema Agyeman had been fired from the show after series 3, when she wasn’t)