I think bands were doing promotional films for their singles much earlier than Queen, during the early 60's. However 'Bo Rap' was the first artistic one, I believe.
Bohemian Rhapsody is acknowledged as the first music video because it was rhe first piece of film recorded specifically for TV broadcast to cover the band's absence - they were on tour.
Other artists have used promo film, but not specifically recorded for use on TOTP by a band who knew in advance that if their song charted, they could not appear in person.
Piffle. There were promo videos in the 60s. There's a great one for "Happy Jack" by The Who, for example. I'm not saying that was the first, just plucking out an example that comfortably predates Bohemian bleeding Rhapsody.