Well it depends, I think the rush job to condemn RDR2 on gender equity on a fucking teaser picture is incredibly premature, especially since RDRevolver had a female playable character and African American.
There was a large African American populace in the Wild West bit if you didn't that era was segregated and racist ...
Though I would love to see a female protag and I'm not optimistic (as per some of my posts on the speculation thread), I agree that this is very premature (especially considering how often Rockstar has key art and such that isn't at all representative of the final game) so I'm going to hold off criticism until we get the trailer.
Also, going off your point, though they have a track record of being terrible with protagonist gender representation, Rockstar has been more representationally progressive than a lot of people give them credit for...numerous black protagonists (CJ, Franklin, the guy from Vice City stories), a Dominican protagonist in Ballad of Gay Tony, playable female characters in every online mode they've ever done (something that Battlefield, e.g., still hasn't done after well over a decade and COD only recently started doing), plus some relatively well done LGBT characters (Gay Tony is fantastic and possibly their best character they've ever written IMO, sorta-kinda-Trevor if you read him that way, closeted Brucie) and a female antagonist in GTA III.
This might not have any bearing on RDR2, of course, but R*'s track record isn't quite as straight white male centric as it may first appear.