I regard "cis" as an arrogant assumption that some people make about other people, often strangers. It is an assumption that is particularly harmful to women and girls (i.e. female people). "Cis" is used to pigeon-hole the following sections of society:
(a) any person assumed to not feel any unease about their body's sexual parts (i.e. their anatomical primary and secondary sexual characteristics) - BUT many girls and women who are NOT transgendered DO feel unease or even distress about their female body parts
and/or
(b) any person assumed to not feel any unease about their gender identity (i.e. their feeling that they are either a girl, boy, man or woman, or their absense of any such feeling)
and/or
(c) any person assumed to not feel any unease about their gender role or, more accurately, their sex role (i.e. the sex-segregated expectations of behavour that society places on people) - BUT many girls and women who are NOT transgendered DO dislike such expectations.
Examples of people who have been assumed to be "cis":
a) people who are not transgendered but who have kept this information private
b) some transmen and transwomen who pass well in their desired gender role but who do not publicly declare to strangers that they happen to be transgendered.
The users of "cis" usually claim that it is just an inoffensive, factual, objective, accurate, neutral term to harmlessly and ever-so-helpfully distinguish between people who are not transgendered ("cis") and people who are transgendered (i.e. trans).
I do not accept that "cis" is these innocent harmless things because when someone labels another person as "cis", they are showing their support for transgenderism ( the patriarchy-supporting political ideology behind gender identity politics, transsexuality, and male crossdressing fetishism). They are buying into a political agenda. They are not primarily showing their support for the lovely transwomen they know who "just want to get on with life".
"Cis woman" and "cis lesbian" are important parts of misogynistic and homophobic transgenderism political ideology and the "cis" prefix is deliberately used to further transgenderism's aim of relegating women to "cis women" and relegating lesbians to "cis lesbians", mere subsets of women and lesbians. Women is becoming a category that women must share with transwomen, whether women like it or not. Lesbian is becoming a category that lesbians must share with "trans lesbians" (i.e. transgender-identifying males who want sexual intercourse with females), whether lesbians like it or not. This relegation of women in patriarchy's gender hierarchy is causing a reduction in women's rights.
One reason why almost all men don't worry about being called "cis men" is because it carries no risk of loss of rights for them.