considering the XBOXOne's backwards compatibility is going to be emulation based, it would be impossible for them to do it without pretty much rewriting Skyrim with a new full XBOXOne/PS4 release..
you really can't just add such a feature into a game, when the gameplay for it on the console in question is entirely emulation based
So if we want to see mods in a console version of Elder Scrolls, then we have to wait for Elder Scrolls 6. By the time it comes out, Bethesda might be releasing it on the PS5 and whatever they call the next Xbox.
that entirely depends on how long the current 8th gen consoles last..
console generations have always been somewhat inconsistent on how long they actually last..
Yeah I mean Nintendo is already revealing their new home console next year which means only a four year span for the WiiU, but this is an extreme case I admit.
No one knows but I feel like most doubt it will be, including me. They keep saying it's an entirely new concept, maybe like a service and hardware combined, but in any case I think it'll be pretty weak and aimed at casuals who ditched Nintendo for their mobile devices, maybe even cheaper than WiiU.
However I think they should make it more mainstream core gamer-ish with power like a PS4 or Xbox One, because I think they cannot get that casual market back anyway.