I'm a lifelong fan of Doctor Who. It's always been a "progressive" programme (a bit like Star Trek in the US in that respect).

I think the recent blip in popularity wasn't "wokeness" per se, but bad writing. Chris Chibnall may be good with detective fiction (the first series of Broadchurch was superb), but I don't think he is very good at writing science fiction. Hence, the Jodie Whitaker era rather suffered (the odd good story, but most were either deeply average or insufferable).

Now Russell T Davies is back, Doctor Who is as progressive as ever, but there's a difference: It's damned entertaining and fun again. The last four episodes have been a blast. I really couldn't give an airborne fornication about the Isaac Newton thing, because it's a throwaway joke in a brief scene that had next to nothing to do with the rest of the (excellent) Wild Blue Yonder episode, beyond provide the basis for a running gag (messing up the timeline so "gravity" becomes "mavity").

Colourblind casting works perfectly well with fiction - see The Personal History of David Coppperfield or Mr Malcolm's List, for instance - and I think that can extend to historic figures when they are flippantly used in something obviously fantastic like Doctor Who. A serious biopic of Isaac Newton? Even then, I'm not sure. After all, we accept Ben Kingsley being Indian (Gandhi), Iranian (House of Sand and Fog), and Jewish (Schindler's List). It's called acting for a reason. :)