If "producing gametes" was the definition of sex, then only men post puberty and pre andropause would be sexed, all other humans would be sexless!

Yes. And even if we expanded the definition to "producing or releasing gametes," it would still mean most girls & women would be sexless 99% of the time during our prime reproductive years. Coz even during the approximately 40 years between menarche and menopause when female humans are capable of maturing and releasing eggs, we aren't capable of doing this all the time - or even most of the time. When not pregnant, on hormonal BC or breastfeeding, girls and women typically release an egg once every 28 days, for a total of 13 a year. Only males can produce sperm at will 24/7/365 and by the hundreds of millions each time.

Heimdekledi has a very male view of human sex. Either due to being utterly clueless about how female bodies work, or from choosing to ignore human female biology altogether coz its realities contradict the spurious claims that "no humans are male or female" and that "sexual anatomy occurs in intermediate forms across a whole range."