There's a concept where I'm from of an employee committee, which is just an assembly of the workers in a particular workplace and a valid actor in collective bargaining. I've been a part of one to negotiate specific policies.
Still a collective bargaining agent, though. Whether or not it fits the US's specific legal categorization of a union, engaging in collective negotiations with employers in an organized manner is fairly universally applicable and positive. "Unions just don't fit this kind of work" sounds a heck of a lot like an excuse to avoid having collective bargaining altogether.