here's nothing wrong about these things and they don't have a fuckin' impact on ones performance in the job.

You're right. Sorry. By using this stereotype as an example, I helped perpetuate it. There are nothing wrong with these things.

For the record:
My pits are usually unshaved unless I need to wear a tank top because I live in Miami and I would smell bad as hell.
I wear my birks every day. I have some heels too. They're for when I feel like it.
I rarely wear makeup (probably twice a month) and when I do it's because I feel like it.

Shave/don't, birks/heels, bare/full-face paint. Up to you. Feminists can be anyone.