Very good point...you would think tech folks would be better at identifying relative vs absolute frames of reference, but then the problem space is heavily propagandized and there is only so much time in the day.
What would an absolute frame of reference with regard to political opinion look like? I'm having a hard time conceiving such a thing, since not only does the range of opinion shift over time, but issues move into and out of relevance unpredictably.
It would be something like "select * from [reality]", except there are various problems like physically manifest reality is not the entirety of it, and our records of reality are often technically from the fantasy realm and the truth has been lost to time without our knowledge.
In the case of allsides.com, they're only comparing ~mainstream US media outlets against each other, but there are many cultures that would consider even left leaning US culture to be insanely far right.
In a more serious world, competent philosophers/linguists/historians/anthropologists/etc would deconstruct and expose these organizations for what they really are: propaganda outlets.
That applies both ways - there's no shortage of religious-rightist cultures on the planet that'd treat many sections of the U.S. right as quite left-leaning.
Even comparing to Europe, the memes that the US is to the right or left of Europe is just grossly wrong, often driven by taking one pet issue like public healthcare and using it as the base, when it's just one aspect of policy and there are others where Europe is markedly more moderate or conservative compared to the US.
Oftentimes those sorts of bias-rating sites also report clearly left-leaning outlets as more centrist than they are, and I wouldn't be surprised if outlets like the NYT get far higher ratings for factuality than they deserve.
