I didn't use sub-D for hard surface modelling for a decade already . Because for hard surface things it's either sbs with bevel node on uv islands or rounding shaders to bake into normal map. Arnold , Octane , Cycles all have them . No hi res models necessary at all. Or sometimes its CAD modelling but often doesn't require…
I wouldn't stake much on it. For decades they did so many weird useless features already but not anything sound for texture painting . Guess it's not that simple.
You can use deferred decals for those chipped paint on the walls. There's also a guide in Substance Academy on how to create such an effect in Substance Painter.