Lighthouses and two men being in the same location don't automatically make me think of penises or gayness but i know we're prone to projecting our inner selves in understanding the world around us so i'm not surprised some other people see it.
It's a film about two men alone on an island with a big lighthouse to take care of, and you didn't sense any any homosexual undertones?
Here's a link for you: https://en.wikipedia.org/wiki/Phallus
Here's a link for you: https://en.wikipedia.org/wiki/Phallus
