Transgender Logic: A Kidney is the Same Thing as a Liver
Elliot's "argument" is satirical, aimed at claims commonly being made by transgender activists. Elliot cites to some of these claims in his tweet thread. Another person making this claim that biology is merely socially constructed is Chase Strangio, one of the lead attorneys for the ACLU, which, once-upon-a-time used to be a principled organization, but has now become unapologetically partisan on many issues.
The problem for Strangio, et al is that biological sex came into existence two billion years before the existence of hominids. That said, basic biological facts don't seem to matter to trans activists like Strangio.