No it is not. Put idiots in a Stanford class they won't be able to do much of the time given to them by Ivy League professor since they won't be able to pay attention
I don't think this is a sound argument. How does it demonstrate attention being not equivalent to time? At best it shows the professor's attention / time / money can be wasted by dull students. Was this ever under dispute?
What was under dispute is whether time is the only real currency. I say it is not and I say it's attention that is the real currency because that's what you really allocate.