Also libertarianism isn’t exclusively right, and anarchy isn’t really left if we take Marxism as being left.
Now you get it. But, we don’t take Marxism to exclusively represent the left. That’s my entire point. Both the left and right have myriad subsets, each of which has differences. Some of those subsets share a handful of values with people from the opposite side of the spectrum when it comes to the bulk of their values.
The hardest question is where do we strike the balance between freedom and equality, they are mutually exclusive and competing. I take your point that overall centrists have the most in common.
I don’t see how they are mutually exclusive at all. Just take the case of slavery. If someone is a slave, he is neither free nor equal to the slaver. If he is emancipated, he becomes freer and more equal in status to his former slavers. On an individual level, he has gained both freedom and equality at the same time. There is a lot of cultural conditioning when it comes to what freedom and equality really mean, and a lot of things that are arbitrarily decided upon as rights or not rights that shape the way we view these concepts.
This also comes up today in the form of a Muslim travel ban. With one stroke of the pen, an entire group of people has had their freedoms limited in an unequal way to all other groups (except, of course, Sikhs, who constantly get mistaken for being Muslim). Other groups didn’t gain any new rights, but now have relatively more rights, thereby creating a new type of privilege for people not targeted by Executive Order 13769. In fact, their freedoms have also been infringed, because now it would be more difficult for an employer to hire a qualified candidate from, say, Syria. In effect, one group has gained privilege by way of inequality, and both groups have lost freedoms.