Exactly what about that demo could Nintendo "not dream to do"?

Overall it hasn't been surpassed for me yet. That's not to say the more recent ZeldaU builds don't look nice (or other WiiU titles like B2 and MK8), but i don't find them anywhere near as visually appealing as the 2011 Zelda demo. To be honest i like how WWHD looks more than the newer ZeldaU build too (bar the excessive bloom) :p

Also worth noting, we have no idea what the framerate on this demo was. We've only ever had off screen footage, which means it may be running at 30fps (wouldn't be uncommon for Zelda). If that's the case, then Bayonetta 2 definitely beats the demo by a country mile. But even without that concession, I think I can get away with saying Bayonetta 2 is the clear winner. Honestly, people are letting the shiny floor and well choreographed usage particles and other effects miss the true technical shortcomings of this old demo.

The Zelda footage we've seen was 2 years away till completion. Plus we've seen so little.

I hope they improve the textures on the mountains, the rest looked pretty great already.

I like WW HD more than the gray and repetitive areas of Bloodborne, but that doesn't mean WW HD is technically more impressive. It's just the artstyle.

That demo was meh back in 2011 and its ugly now.

It had some technically impressive aspects like the realtime shadows,dynamic lighting, reflections and particle fx in the smoke debris but as a whole package it never set any benchmarks imo. Visually its below Nintendo's standards to be honest, there are better looking games on the Wii U.

Are any of those better looking games as technically advance? Nope.

Ah, so not graphically, but personally to you they haven't beat the visual appeal. 

Not yet, I am sure they will make a game on par with that, but looking at Zelda U I dont think it will with the art direction it is/was going for.

the demo was never impressive to begin with. Looked about on par with God of War 3 and for a next gen console, I expected much more.

Gotta say I found bayonetta 2 to look just as good as that, if not better.

That, along with some other first party games (mario kart comes to mind), look beautiful, and I imagine Xenoblade X will look great as well. I think some posters are getting a little too down on the visuals of the Wii U! :p

I think Bloodborne looks nicer than all of them I was talking overall though, not only on a technical level. If I were talking specifically about the latter then I wouldn't have many good things to say about WWHD. It's an excellent remaster, but its GC foundations are pretty clear (especially the geometry).