In point 1, they give a definition of sex based exclusively on gametes. While this can be a useful definition, they don't acknowledge that it is a choice, and that other choices, such as definitions based on chromosomes or genitals, exist and are used. They insist that there must be only two sexes because there is no "third gamete" even though it is not necessary when following their definition. One could meaningfully categorize hermaphrodites as a third sex in this system, but they arbitrarily dismiss that out of hand with no explanation. "Developmental variants" are similarly dismissed, on the completely arbitrary basis that they are rare. Permanently sterile organisms, which produce no gametes and thus are neither male nor female by their definition, are not brought up at all. They also take a jab at the term "assigned female at birth" and (hilariously) declare that doctors are directly observing "biological reality" rather than external genital structure (and they aren't observing gametes either, for that matter). This last one in particular is a point I normally only see from the most ardent ideologues.
In point 5, they consistently conflate race and the idea that people in different places are genetically different from each other in some ways. They also present their opponent's position as one that claims that there is no difference between population. They generally fail to argue against the point that race is a social construct and instead point to various means by which it can be determined. They seem to think that the ability of an AI to determine race from an X-ray "proves" race is somehow a natural kind; rather, it shows that humans can teach AI what humans think race is. This recent article from the HN homepage also contradicts some of this section's sourcing: "Self-reported race, ethnicity don't match genetic ancestry in the U.S.": https://news.ycombinator.com/item?id=44201736