I mean, you’re just flat-out wrong. You should listen to those lectures, they would do you some good.

projectnettie.wordpress.com

In mammals, there are two types of gamete and two classes of reproductive anatomy. The male sex class produces many small motile gametes – sperm – for transfer. The female sex class produces few large immobile gametes – ova – and gestates/delivers live young. […] Biological sex does not meet the defining criteria for a spectrum. […] Not one of these individuals represents an additional sex class.

(Because it sadly needs to be said, I’m not “citing wordpress”, I’m citing a project created by a PhD Developmental Biology with many signatories with relevant credentials, which she chose to host on wordpress)

Bringing up hyenas is ironic, because it’s a great illustration of why sex is defined that way. Female hyenas have a pseudopenis. But how can we tell that they’re female? Because they produce the larger of two gamete types! Without the gametic definition of sex, there’s no way of talking about “female” across species.

Sex is defined by gamete production because it’s the only coherent way to describe the reality that biologists have found across all anisogamous species.

Sex currently has 2 plus several proposed additional definitions.

Biology has one definition of sex, that has remain unchanged for well over a century, and has no serious attempts to change it.