5D3 is no sharper.
However, at least the 5D3 delivers a softish '1920x1080' without that nasty moire and aliasing, so it does a WAY better job and can look a bit filmic, this looks super video-ish. This is not a good results. But then gain Canon marketing MBA loves LOVES their internal market segmentation and purposeful crippling (other brands and products capabilities and threats be damned).
Part of me thinks that looks to have a bit worse aliasing than the 5D2 even.