It may have more to do with compartmentalisation than anything else. Economists focus their attention on their own sub-disciplines, so the micro guys don't pay much attention to what the macro guys are doing. I'm not sure that's especially unusual in any intellectual discipline though.

Secondly, macro is what most people think of when they think of economics. So laypeople talk about the failings of economics when they're really talking about fairly small parts of the discipline in the grand scheme of things.

As to why economists don't pick up on this more often, I'm not really sure. Part of it is that debates on the epistemological merits of different methodologies don't really get a lot of play among the general public for some reason.