Some Like It Hot (1959)

This historic movie was controversial because it featured two cross-dressing male characters; they pose as female musicians because they need to escape the mafia. I didn’t find it entertaining, just awkward and silly.

Your mileage may vary! According to Wikipedia, it “opened to critical and commercial success and is considered to be one of the greatest films of all time.” That’s why it keeps cropping up on lists of “must-watch movies,” and that’s why I watched it.