No, I know a lot of women who don’t do any of those things and more who do only some of them, and rarely, and even more who occasionally do them all but just very seldom and only for practical reasons or to experience something different.
I don’t think being fit within reason is vain. It’s healthy. Why can’t you imagine not straightening your hair? I don’t think it’s vain if you do for practical reasons, say if your hair is just hard to keep neat otherwise, or because it’s expected at your job, but haven’t you ever just wanted to try something different? Myself, I’ve had more styles than I can keep mental count of. I get bored. I wish mine would stay super-curly just so I could try it for a year or so. I don’t think that’s even vanity. It’s not as if I change my hair to be stared at and admired or as a way of being better than other people. I just like to express myself. And when I go natural my hair is drab and stringy and looks unprofessional, ragged and weak. And my skin is OK sometimes on its own but I don’t want to meet with someone who can affect my life (like a job interviewer) with zits showing. That’s just self-preservation.