The market is the will of people. Any alternative thing is going to be more incorrectly adapted to the demand from people.

The market is one-dollar-one-vote. If you start with an equitable distribution of wealth, then sure, it's the will of the people. But if you start with wealth being disproportionally skewed towards a very small class - as is the case in every real-world developed economy today - the result is oligarchy, not democracy.

The problem with mainstream economic right is that it ignores that, or assumes that markets will eventually equalize naturally somehow. The problem with mainstream economic left is that it wants to strangle the market instead of freeing it from oligarchy.

An oligarchy serves itself from the regulators to keep its power. In a free market they would not be able to abuse that power to get privileges.

So the problem you see there is mostly a regulation problem, not a wealth inequality problem.

There is no mainstream economic left.

"Left" and "right" are relative terms, not absolute. Mainstream economic left is whatever the majority of people who are left of center hold to.

The economic left isn't allowed into the mainstream of politics.

"Left" is not a synonym for "socialism".

Socialism is a word that can be defined in absolute terms. But left/right is defined relative to society as a whole. Whoever is left of center in political mainstream is the economic left, by definition.

Seems like you're trying to define words in a way that makes the actual state of affairs in the USA impossible to describe.

No matter if all leftists are removed from society, leftism must still be said to be half of what remains.

Nothing in mainstream USA politics should be described as "economic left."