Chart is very tough to follow.
They have the typical mistake of claiming Democrats supported the Civil Rights movement, when in fact, they didn’t.
I do like how they accurately state that Sen. Byrd who, “most closely resembled like Palpatine.”
no way to tell what the author means by “far right”
and besides, as is clear on the Democrat side of the chart
party identification IS NOT synonymous with ideologicl identification - for instance many “far left” Marxists have run/obtained office as Democrats
altogether I think there is a leftward political bias in the authors’ chart