There was a lot (even a Neowin FPN) and it was largely inaccurate (only 1 game Lococyle used PCs and the dev readily admitted to it). It is still referred as an evidence of XB1's weakness every now and then,
I don't recall much negative press about it. Demoing on PC at e3 has been the norm for many years now. The e3 demo of Halo 2 was running on PC too.
But i do recall some fans saying One games were looking better than PS4 games and people telling them pretty much all the games were running on PC at e3 so it did not really matter.
We'll see when the real games hit the stores.
see this (and note the timestamps),
X1 demos were running on high powered PCs.
Here's the accusation,
Here's the response:
There's also this 'games reporter' noting that some demo kiosks crashed to a standard-issue Windows desktop (like what you'd have on a PC) rather than what you'd get for a console running Windows 8. https://twitter.com/...967744808185857
One developer responded saying "We just didn't have time to make Xbox1-native versions so we just ran the PC version because we wanted to showcase our game."
-- so, what's the summary? --
We know for sure the demos weren't running all running on XBox One hardware. Some of it was explained to be running on 'pc hardware similar to an xbox one -- development kits' and that despite their considerably more powerful hardware, the machines should have performance similar to the shipping consumer version of the XBox One. Other demos just were the desktop PC version running on pretty good quality hardware because that's all the developer had to showcase.
Make of that what you will.
Nothing was blown out of proportion.
It's just that some people were religiously hurt when the news came out. Whether first party, second party or third party doesn't matter.
I just hope both consoles run games at slightly higher resolution than 720p at least.