I interpreted the "What is 'sometimes sexist attitudes' doing there" as outrage over it being mentioned. I did not thought it was disagreement, because the article has some quick explains on which part of memoirs made them thing that.
> I'm pretty sure he wasn't sexist in the even narrower sense of thinking that women simply can't do the things that traditionally used to be men's jobs
I think that part is addressed by "generous support for women academicians", support he gave to his sister and "unwavering respect for the many talented women he supported" and "support to the Blake scholar Jenijoy La Belle" all in the article.
The article basically goes out of way to point out instances where he was supportive to women with ambitions.
Offtopic: To me personally, mentioned negative attitudes mostly spoken to having certain sense of entitlement or naivety around bar women. He kind of expected them to be different species. The one where a girl falls in love with dude she just met and will have sex cause the guy she knows for 10 minutes is so awesome. Obviously it does not work like that, leading to disappointment and resentment over having to basically pay for sex.