Just made it through 26 pages so most of the points have already been made. A few that haven't...
On "blackface is different because it was done by privileged white people, while drag is done by oppressed gay people" - Many of the original "minstrel" performers were Jewish - notably Al Jolson. In early twentieth century America Jewish people were privileged compared to Black people but were not overall a privileged group. So the "punching up/punching down" discussion has been had around blackface as well. This is a senstive topic which deserves more than the quick comment I am giving it and there is further info here, but be aware this page includes images of blackface and quotes contextualising blackface that, while I do not believe they are intended to be offensive (or I would not post the link) I recognise may nevertheless cause offense https://www.jta.org/2019/02/06/ny/jews-and-blackface-its-complicated
On Strictly specifically and drag more generally, aside from the generally problematic nature of an "artform" that depends on its performers dressing up as a specific, real-life group of whom they are not a member, having a drag artist as one of the couples has resulted in an opportunity that would usually be given to a woman being taken by a man. I appreciate this would also be the case for a male same-sex pairing but somehow it feels more insidious and erasing of women when the man in question is "performing" a female role.
So the more drag acts are prioritised, the fewer opportunities there are for female performers and the fewer representations of women are actually being done by, well, women.
RPDR is basically a sausage-fest with a very occasional token woman. Without drag, having a show that excludes women to that extent on prime time TV would be being rightly challenged and criticised, but the faux-female, "diverse" nature of drag makes this pushing out of women less obvious than it would be if all those blokes were dressed in T shirt and jeans and doing Paul Merton type bloke comedy. Because the diversity is there, it's just that the actual opportunities are all going to men. As a PP said, do you think women wearing the same outfits and doing the same jokes/acts as drag queens would be anything like as popular?
It's important to remember that for all the "it's honouring women, it's satirising gender stereotypes, it's empowering LBGT+ people", drag is an almost exclusively male artform, in which women - our bodies, our experiences, our lives - are present only as material for the male performer, and shown not as we might present ourselves but as his interpretation.