Thank you, cliff notes from 1984.
Left and right as a political spectrum comes from the early days of the French Revolution, where the people who thought that the relationship with the monarchy could and should be repaired sat on the right, and those who believed the monarchy could and should be abolished entirely sat on the left.
The idea still extends accordingly: the left wing believes is a flatter society with fewer differentiation between elite and working class, while the right wing believes that society should have some kind of meritocracy and a social hierarchy is a sign that this is working.
As you have pointed out, through a certain set of eyes, we can recognize that certain practices seem to recur in governments of both left and right wing implementation - as, indeed, George Orwell noticed that these practices permeate through governments that one might even consider to be moderate.
But that does not mean left and right have been blurred to the degree you are suggesting. Nazism believes in the rule of the Overman, which is not a left wing thing. Communism believes in the rule of a global collective, which is not a right wing thing.
And it's about time you worked that out.