I have never had too much trouble with dust, even when there are more vehicles than I want, like last spring when everybody discovered hiking
In a motor vehicle, you keep up with the vehicle that's making the dust, so you get to experience it for a long time.
I don't know what to say to someone that doesn't have a bike they can ride on gravel. It's a big expense for something you might not like. I used my road bike with the biggest tires it would take at first, 30mm or something. Then converted to a different old bike before finally getting a dedicated gravel bike.