Well I agree and disagree :) as always it depends. I think it’s clear that especially on slow mobile connections people will close a site quickly if they don’t see results and this in turn yields lower sales for example. Also, Google will factor Speed into its algorithm. So you will lose traffic if you don’t optimize. At the same time, people at home with broadband wouldn’t care less.

That’s actually a core reason for slow pages. People in offices with large monitors and huge bandwidth develop those sites