Chuck Wendig wrote an excellent list that is so excellent you need to read it fully.
On the other side of things you have slut shaming, where women are made to feel lesser for their sexual choices (or, worse, for being sexually assaulted). It’s easy when criticizing covers (as above) to make it sound like slut shaming: “Those women are too sexy on those book covers, they should be all covered up LIKE PROPER MENNONITE MOTHERS.” The difference, I think, is between being sexual and being sexualized. The former is under the character’s (or author’s) control — the latter is controlled by someone else. Criticizing the sexualization of women has merit; criticizing the sexual nature of women is fucked up (and is slut shaming).Read more here
Also apparently I somehow missed Seanan McGuire saying smart things about this whole issue. (And I don't know how I missed this since I
As for the appearance thing...yeah, people often like to be told when they look good. But women in our modern world are frequently valued according to appearance to such a degree that it eclipses all else. "Jane was a hell of a science fiction writer...but more importantly, she was gorgeous according to a very narrow and largely male-defined standard of conventional beauty."Read more here
Here is another article that gives examples of what has happened to female writers and science fiction events. It's pretty terrible.
The first person I met was a famous science fiction writer, the Guest of Honor. He asked me what I did, and I told him I wrote steampunk paranormal romance. He scoffed and said that in the grand pyramid of writers, I was the bottom level. That I wasn't worth, and I quote, "the shit on his shoe" because I didn't have quality science in my books and just wrote "vampire porn". He said that women like me were ruining his genre.Read more here