TBH the subtext in your post was: “I’m having trouble getting some action”. I’ve not encountered this ‘repression’ of which you speak. I’ve no idea about the men, but women are about as ready to go horizontal jogging as in any other place I’ve lived.
Young Taiwanese people can be emotionally immature due to academic pressure, but by the time they hit their late 20s they’ve mostly got it out of their system.
I used to work near Zhubei. I really liked it there, but I don’t remember anyone speaking English much (Hsinchu I guess is better in that regard). I’m guessing your success in the dating pool will be heavily dependent on your Chinese ability.