One of the main reasons series why series like Downton Abbey have become so popular is historical accuracy. Downton had Alastair Bruce on set 100% of the time exclusively to maintain this. His excellent work was in no small part responsible for the series success.
Then contrast this with the 'racially transparent' casting in Bridgerton. It is historical fact that there was no 'black duke', and the suggestion that the Queen at the time was black is also false. Additionally, although there were freed slaves in London at the time, it was not until 1833 that Britain abolished slavery and permitted free movement of black people in London - in particular in high society.
So why do it? Are we to see the next Season of 'The Crown' with a Japanese Queen Elizabeth? Perhaps a Mongolian or Peruvian Lord Grantham were there ever another season of Downton? Obviously not.
When the absurdity of political correctness overtakes historical accuracy the suspension of disbelief is the first thing that suffers. My confidence in Netflix has been severely tarnished.