The transgender movement ignores the distinction between gender and sex all the time. Funny how we don't see you criticizing when they do it.
For example: birth certificates list sex, not gender. But many of them insist on changing their birth certificate to reflect something they were not born as.
Pronouns also reference biological sex rather than gender, since throughout history they were automatically applied to a baby upon its birth.
This is actually quite funny because in actual usage pronouns are almost always referring to someone's gender.
Transphobes overestimate the frequency of misgendering because they wildly underestimate the number of trans people who are read as the gender they present as. Even in the era of history preceding the invention of hormone replacement therapy, there are
quite a few examples of likely trans people who lived as the the opposite sex, and there are doubtless many more who were never outed.
People don't generally assume that random people they meet are transgender!