There is no “play” here. Pedantically correcting people isn’t fun. There is no humor in it. Puns require humor/play. Also, correcting people to say that banana

There is no “play” here. Pedantically correcting people isn’t fun. There is no humor in it. Puns require humor/play. Also, correcting people to say that bananas are berries doesn’t even acknowledge a second meaning of berry. It suggests the meaning they know of is wrong. I’m aware we’re talking about a technical meaning and a commonly-accepted meaning, but the assertion is suggesting the commonly-accepted meaning is completely invalid.