What's the issue? Even if it literally is the BBC being PC, what's wrong with having a figure that girls can look up to who is a leader and sciency?
Like I get that people are put off by PC gone mad kinda stuff but this is literally just a white woman acting where white men have in the past. This is no revolution of some trans-mixed race-asexual-furry playing a character who's name may no longer be Doctor because of the strong cis-male association. How do people get so triggered about such a minor thing (not you necessarily but some people online at least)?