Which also equally implies the opposite: you can believe in something that doesn't affect you. It seems like you haven't thought this out very well?
IOW, this seems to be yet another example that doesn’t support your view nearly as well as you seem to think it does.
As in the case of gravity, there are often competing explanations. For example, we currently think there is no field of gravity, but space-time bends due to mass.
Imagine someone living in 1850 arguing: "We already know what gravity is. End of story." But they would have been wrong in a way that would eventually affect navigation, communications, astronomy, and our understanding of the universe.
Before relativity, very few people would have guessed, after being lost and injured during a hike in the desert, whether you’re rescued could depend on the fact that clocks run at different rates in orbit.
The interesting lesson is not just that Einstein replaced Newton. It’s that a genuinely new explanatory theory revealed consequences that nobody had previously imagined.