Would it be terrible if employees could fire their employers arbitrarily?
Both parties have freedom in this arrangement, but we can find examples of both employees and employers with weak negotiating positions. I don't think that invalidates the benefits of freedoms of association.
To your point about business being bound by constraints, they absolutely are bound by the niche they operate in. As markets change, world events unfold, competitors appear, decisions are made, companies can struggle and fail, yet are typically unable to pivot.
Consider a company that makes ICE cars that can't follow the market into making EVs. Or a company that has never had competition might be in the stranglehold of "this is the way we've always done it" when a fierce competitor emerges, and won't adapt.
True, most employees typically don't have equity (so they don't share in all the upside), but they also aren't married to the company when it looks like a supertanker headed for an inevitable collision with a bridge (getting wiped out on the downside).