When I talked about effeminacy, I was thinking mainly in their appearance and mannerisms.

It's not your concept of "effeminacy" I'm taking issue with. It's the concept of "effeminacy" that has been put forward by men for donkey's years that I think a lot of us women have just blindly accepted and parroted. As you pointed out, this concept is based solely on

appearance and mannerisms

Which reduces women to two-dimensional beings who consist of nothing but surface appearances and superficial mannerisms. Sounds pretty sexist, misogynistic and dehumanizing to me.

Yes, these men's "appearance and mannerisms" might seem to be "effeminate" in some people's view coz they are exaggerated versions or caricatures of the appearance and mannerisms of some members of the female sex. But I think the segment of the female sex they model their appearance and mannerisms on is an incredibly small segment of the worldwide female population, one that's not at all indicative or representative of how the vast majority of female people appear and behave.

These guys base their idea of being female on the sexed-up public personas and stage performances of women like Marilyn Monroe, Jayne Mansfield, Judy Garland, Cher and the Kardashians - not on the reality of what those women were/are really like behind the scenes. From what little I've seen, the Kardashian women might look a certain way, but they tend to speak forthrightly in normal tones rather than in high-pitched breathy voices, and none of them are constantly engaging in fluttery hand mannerisms and constant head tilting and simpering that these supposedly "effeminate" guys tend to evince.

Also, the female sex symbols and pop stars such that these men base their idea of womanhood and femaleness on never were, nor are they now, at all representative of what the majority of the world's women are like or have ever been like. Why are none of these guys basing their idea of womanhood on famous and notable women like Golda Meir, Shirley Chisholm, Bella Abzug, Indira Ghandi, Temple Grandin, Angela Davis, Janet Reno, Mother Teresa, Hibo Wardere, Ruth Bader Ginsburg, Marie Curie, Donna Strickland, Svetlana Alexievich, Tu Youyou, Malala Yousafzai - or on these men's own mums, grandmums, teachers and neighbors?

Even if we say okay fine, let these men take their idea of womanhood only from film and pop stars, why are these men still exclusively focused on such a narrow group of women in film and music? Why the sole focus on women who were publicly presented as widely perceived as big bosomed sex bombs, rather than on actresses like Eve Arden, Glenn Close, Judy Dench, Linda Hunt and rockers like Patti Smith, Joan Armatrading and Annie Lennox?

I'm old and as a result have known and observed thousands, probably tens of thousands, of women IRL. Only a handful have had appearances and mannerisms that come anywhere close to the ones displayed by these men that, in my view, are inaccurately labelled "effeminate."