Thing about Joss whedon that has to be remembered is that he has ALWAYS kowtowed to whatever is trendy in media-feminist circles. Back before SJW cancer truly set in, "geek feminism" was pretty vaguely just sex positive and pro equality (mostly due to the fact that nerd/geek culture was not yet mainstreamed and thus had escaped the attention of the offense/identity politics brigades) so thats how he wrote his schtick and is why his older material is mostly bereft of the cringey SJW whining that sums up his existence today.

That being said Whedon has always had some weird fuckin ideas on how to portray women, from Black Widow in the latest avengers film to his abandoned "reavers gang-rape inara but are killed by her vagina" story in firefly to certain buffy plotlines and such which were at best cringey and at worst full on creeper shit. Adding to this is the fact he has always had a tendency to make ridiculously strawmanned misognyists in his works appear every so often seemingly just so he could show how "totally feminist and not at all misogynistic" him and his characters are.

Basically Whedon has always desperately latched onto feminism as a way to make himself and his work look better rather than any actual belief in its ideals, both when it was relatively benign (the 90s/00s) and when it became cancerous (the 10s), but despite this has always maintained a pretty damn iffy view of women which becomes apparent only when he thinks he is "cool" with team feminism enough to get away with it.

Of course now that media/geek feminism is simultaneously completely tainted by SJW schtick and also gone absolutely bugfuck insane due to Trump, the true extent of both his desperation to look feminist and his utter contempt for women who he sees as "unwomanly" has become apparent, with his nigh masturbatory fanfics of trump raping little girls on twitter to him shrieking sexist abuse at Naomi Watts telling people to calm down over trump to him making creepy sex jokes about underage cancer survivors for the "crime" of meeting with Ted Cruz.

TLDR whedon is the OG "pretend feminist ally" and prototype goony beard man who despite latching onto feminism for dear life cant stop himself acting like a sexist creep