I asked Copilot this exact question and it says Python and JavaScript are the most popular for vibe programming. Take that with a grain of salt.
Taking the conversation further, basically languages in the TIOBE top 10 are your best bet. Copilot claimed that it's generally better at generating solutions in those languages than languages not in the TIOBE top 10. Don't know whether that's true or not, but it makes sense, and it was straight from the horse's mouth!
FWIW, I've had a lot of success vibe coding with Python and JavaScript.