Comment by tdb7893
The graph isn't "agrees with Republican" and "agrees with Democrat" as the axis (I also would say you can agree with people and still be a free thinker, viewing positions as independent doesn't really make sense, there's underlying ideology that heavily correlates them but all of this is besides the point). The idea that the far left is agreeing dogmatically with the democratic platform is clearly factually incorrect to anyone who has met people actually on the far left (they rarely even agree with other people on the far left) and a similar thing can be said about the far right.
The really obvious example of this is look how much of a thorn in the side of the Republican Congressional leadership the far right has been. Agreeing rigidly with a party will not put you at the edge of the graphs at all (for most parties globally it would put you somewhere in the middle)
The graph X axis could just as well have been labelled "agrees with Republicans" and "agrees with Democrats"; perhaps it would've been clearer that way. But really, any polarization axis would've worked.
The ideal graph would have two opposing labels dynamically generated according to the beliefs of the reader to be along a polarization axis for which the reader exists in the middle.