>Hm, where is this imposition of power? I see what could be clearly called bargaining.

Isn't this ironic? The whole point of a union is collective bargaining power; individual employees do not have any bargaining power so how exactly is musk engaging in bargaining? With whom is he bargaining?

>but comparing it to "sexual favors" not only absolutely meaningless,

They're both examples of coercion by someone with power over a subordinate, they both involve trading your body (in the form of labor or sex) for money (or some sort of compensation), and they're both generally recognized as exploitative. These are three obvious features that make them analogous propositions.