Sex scenes with trans women in film and TV have historically been a spectacle of objectification, fetishisation and at times, dehumanisation. Their characters are broadly one-dimensional, transactional and inconsequential. In short, up until fairly recently, the trans femme experience on-screen has been depicted by a lot of trauma, violence and overcoming great obstacles and not a whole lot of joy and enjoyment. 

This echoes the experiences of women (both queer or heterosexual) and gay/lesbian/bi on screen, who often fall prey to male-gazes and tired stereotypes that do little to advance plot, character arc or any of the other stuff that, you know, makes a film actually good.

Queer sex, particularly, often comes out in the wash this way. As if queer sex is only seen as compelling or meaningful when it follows intense struggle or hardship (yawn!). There is very little agency, autonomy and self-determination when it comes to demonstrating sex on scene. 

That being said, these four scenes have gone down in history for breaking the mould and showing that trans women and femmes can have sex on screen that is pleasure-focused, consenting and meaningful.