Yes and no. An upgrade to a 64-bit exe would only benefit Windows 7 users if the engine is still DirectX 9 because Windows 10 simply can not use more than 4GB in DirectX 9 games regardless of whether you have a 32-bit, 64-bit or hypothetical 512-bit exe
. Windows 10 is always 4GB only if/when DirectX 9 is involved.
It has not been 100% confirmed to this day AFAIK that the renderer has been upgraded to DirectX 11. It is very likely because some of the new graphics features are supposed to be requiring DX11 but who knows… maybe Bethesda kind of "grafted" the effects on top of the DX9 engine with workarounds.
If the renderer is still DX9 then the 64-bit exe will do pretty much nothing for Win 10 users so let us hope that someone can confirm DX11 beyond a doubt real soon (does this YT guy say anything about DX9 to DX11 in his videos?).