In some cultures letting a gay or trans person live is unconscionable, there is no link between how random cultures feel and morality. There is no reason to base a progressive and modern society on cruel social traditions.

If you want to change your gender at this exhibit in Australia then you are free to do so, if your cultural baggage makes the idea disgusting to you then either work on that or choose to miss out on this art and many other beautiful things because maintaining hurtful traditions is more important to you.