So spacetime (interactions between mass, space, and time) are required for any sort of precision explanation. If "extreme" means planet size masses, I guess, but I generally consider our solar system pretty normal. However we cannot explain the planetary motion of mercury without relativity, so define your extreme.
But sure, newton is good enough to handle most ground based scenarios where we only care about forces at low precision.
But sure, newton is good enough to handle most ground based scenarios where we only care about forces at low precision.