Most unions that have survived 40 years of anti worker propaganda are huge, yes. But they don't have to be. One thing I'm hoping comes out of this recent union revival is an exploration of different union types and sizes, to find new models that work well.
You seem to be rather confused about how unions actually work, this is one of many comments from you in this thread that kind of reads like you got all of your exposure to unions from a Ben Shapiro video or something.