I agree with you, I’d laugh if someone was telling me this!
However, I can assure you your monitor can display a more accurate signal if you’re downscaling a 4K render into a 1K display, and actually, this is the minimum downscaling necessary to accurately sample the signal:
NB: antialiasing only consists in finding ways to sample the signal at a lower frequency than the Nyquist one in order to save computational power, while trying to minimize the sampling error, but it can’t fully eliminate the error.