I use Reaper for mastering. It has built in 2x or 4x oversampling available for any chain of 1 or more FX.
Generally oversampling is useful for non-linear FX such as saturation or dynamics processing of any kind to avoid aliased images of processed audio to be reflected off the Nyquist frequency and appear in the baseband audio as non-harmonic artifacts.
So I don’t upsample the project. But if this feature wasn’t available, I would definitely upsample.