Why is there an assumption that the left must support her just because she's trans? Or black, or a woman, or whatever?
Because that's the standard you set.
No, not at all. That's the standard YOU expect. We support trans rights, gay rights, and women's rights. There's a difference.
We supported the trans woman for the Assistant Health Secretary's job because she had the education, credentials, and experience to make her the best person for the job. Jenner has NONE of those things.
YOU expect us to support any candidate who isn't a white CIS gendered male because "minorities". We're not under any obligation to support any "non-traditional" candidate just because they're not a white CIS-genered male.
We should ALL be evaluating candidates firstly on the basis of their qualifications, secondly based on their platform, and then on other factors. I wouldn't reject a trans candidate because they're trans, but I sure wouldn't vote for someone whose platform and qualifications were lacking just because they ticked off some minority box, without them.