> None of those are left wing (or even “more frequently associated with the less right wing of the two major parties in America”)
These are quintessentially left-wing in the context of the past century of American politics.
> Fascist corporatism is not left-wing
Of course it is. It was deliberately designed as an alternative means for achieving socialist ends by socialists disillusioned with Marxism. It's always characterized itself as a "third way", but still one that seeks to radical change society through political force, and in opposition to those who want to conserve the status quo and admit change only through gradual development. The former is the traditional definition of "left" and the latter of "right".
> No, you’ve confused libertarianism/minarchism with conservatism. Conservatism, as an “actual political philosophy”, or rather a broad political orientation which is not a single unified philosophy but is conprised of distinct philosophies tending in the same broad direction, arose in response to and is exactly resistance to the downward, equalizing, leveling drive of enlightment liberalism.
It should be clear that in a US context, I'm referring to specifically Anglo-American conservatism, which does differ from other varieties in its devotion to particular forms of constitutionalism and to economic liberalism, i.e. the Burkean variety, and not to continental forms of conservatism which have had little historical significance in America.
> The on-and-off rhetorical appeal to libertarianism by the Right especially when out of power is, exactly, a matter of “whatever faction a particular political party happens to be pandering to at any given moment.”
The problem is that you're presumptively conflating party with political philosophy even in levying this criticism. In terms of US presidents in my lifetime, I'd regard Carter, Reagan, and Clinton as conservatives, both Bushes and Obama as moderates, Biden as being on the center-left, and Trump as being on the far left.
Actual political philosophy cuts across party lines -- the parties themselves are just coalitions of factions that are mainly aligned due to mutual tactical opposition to the other coalition, and not by any shared worldview. The nature of these coalitions has far more influence on what rhetoric they employ on the campaign trail than it does on what actual policy positions they take once in office.