There is such a thing as diminishing returns and post processing effects matter. I find 720p still acceptable, 1080p is more ideal, but north of that becomes less important.
As an Xbox One owner I gladly trade resolution/super sampling for higher graphics settings and performance. For example, I was playing the Battlefield V campaign and the resolution looks fantastic, performance feels rock solid, but the LOD settings and pop in is disappointing. I wish it had a more aggressive dynamic resolution in exchange for better graphics settings.