Unfortunately union / labor movements in the US suffer from a big problem: due to historical circumstances they’re very combative. The labor movement here never grafted the idea of being business oriented on behalf of workers into the movement (like in Germany) rather, they treat the business as the enemy pretty much from the outset.

Some of that is indeed earned by the businesses reputation, but ultimately this is what I think spurred the decline of union membership in the US because businesses don’t get a lot if any value out of having a union around and the organized workers often find the benefits stagnant after some time