> Why are tv shows like "Sex Education" allowed to show full-frontal male nudity, but not female?

It's a choice.

> Years ago it was the males form you couldn't show nude... The only tv show I watched that shows more female nudity would be Game of Thrones.

I can't say I've kept track this, but I do recall Oz infamously had it and that was back in '97. Likewise, I recall Ash vs Evil Dead having female nudity, as well as Altered Carbon, Westworld and a few more. Like, it isn't something I keep track of, but it is something they can do and choose not to. Either for reception, artistic or some other reason.