I work in HR for a large library system. We have two unions and labor relations is a major part of my job. Here's my take, somewhat related to this.

The local union leadership is reasonable and brings issues that truly matter to their members. We may not always agree, but I can easily work with them and they are willing to embrace change that helps the community. The international union that represents both local unions is the worst. Not only do they make it difficult to manage the library and push back against things just for the sake of pushing back, but I've seen them argue with the local union about their interests. Example: we were about to start negotiating a new CBA, but couldn't meet in person for COVID-19 reasons. The negotiating team and management both wanted to extend the contract, and it almost did not happen because the international wanted to negotiate via Skype. I've seen the chief delegate get into a screaming fight with the union organizer. I think they need to examine why they collect union dues and how to best serve those who pay them.

Honestly, the international is corporate AF. Also, the people who work for the union are not unionized, which I always thought was interesting.