Are Bert and Ernie really gay?
Bert and Ernie are puppets. Puppets typically do not have sexual organs, and if they were designed with them, they are non-working organs. They are also not alive, I know they seem alive when they are walking around and talking, but that’s some guy controlling the inanimate objects that are Bert and Ernie.
The characters are for children. Few children are interested in sexual concepts, mainly because they haven’t reached puberty yet. As a result children’s characters tend to be a-sexual, puppets in particular tend to be a-sexual. Bert and Ernie live together to demonstrate a strong friendship, to encourage children to be open to other people, and not in a sexual way.
Not only are Bert and Ernie not gay, but suggesting it is like asking if the Empire State Building is gay.