They don't use 24fps because that argument just doesn't make any sense, and they know it. Like I said, this is not a technical argument, it's not because you film something at 60fps you can't make it look "cinematic", whatever that means. And films at 60fps will be standard very soon, so that statement won't even make sense anymore in a few years...
I don't see why you say higher framerates will be less needed because technologies will give variable framerate. A stable 60 fps should still be a standard imo, even with more variable fps, and if it's variable, lag will always be noticable.
Yes, it's not only marketing that was/is the problem for the wii u, but seriously, if you have to keep explaining people it's a new console and not an 'upgrade' for the wii it's quite clear marketing has failed. I never(/barely) saw a commercial for the wii u in my country, while I'm pretty sure even the gods saw commercials for the ps4/xbox1.


