See I remember S5 having no LGBT characters. Someone pointed this out to Moffat, who was very unhappy that he hadn't even realised and then promptly introduced a lot of gay characters in S6. So that's a showrunner who had a blind spot (hi unconscious privilege) and then set out to fix it. Whereas apparently they talked up the presentation ahead of S11? So they weren't unaware, they just... didn't do much. :(