OSM’s attribution is non-negotiable. It’s part of the Open Database Licence and also the Contributor Terms under which individual mappers agree that the OSM Foundation can sublicense their work. There is no legal way around it save for contacting each individual mapper for permission… which is clearly impractical.

By contrast, Mapbox ask for a credit as part of a commercial agreement, which by definition can be negotiated away. I guarantee if you call up Mapbox and offer them enough money, they’ll flex on their logo requirement. There is simply no legal way to do that with OSM.