Fakeclaiming another BD class as BD on the stand shouldn’t be considered gamethrowing, since it’s public and something completely different from lying to just confirmed BD. Especially if you’re a heathen which actively triggers players to NOT claim their exact BD class.
If I want to claim Hunter, because I have deduced that there is a low chance there is one (with all available claims out there) to avoid a nightkill or because I’m Prince for instance, I would want to able to do so to further my win condition.