When I talk to colleagues in tech about unions I hear a lot of misconceptions, seemingly based in stereotypes about what unions are for and who they serve. People often seem to think of unions as being purely blue-collar operations, and this just isn't true. For example, I've had people tell me that they don't support unions in tech because they'll be "paid less", or less competent engineers will be promoted faster.…
Unfortunately, through my own experience being in one & observing other unions, they often end up serving the organization of the union itself. They may still work for the workers, but also end up making decisions that are better for the union than for the workers.
Right now, my kids are learning remotely. However, the school district has encouraged teachers themselves to still report to their classroom to teach from there because seeing that environment lends at least a little bit more normalcy to the experience. You might agree or disagree, but the teachers have the choice. However, teachers are being told & subtly bullied by the union into not doing this for some vague justification that it weakens the union. At least one member I know of has said they're teaching like this, but they hope the union doesn't find out because they would "get in trouble".
I think unions can be a good & important tool in equalizing the power imbalance between an individual worker and their larger employers. Unfortunately, those who seek & rise to position of authority within the union structure are often those who end up seeing the union are a "good" unto itself rather than serving the members & their wishes.