Many of my family members belong to a union, have belonged to a union, or own companies who have become unionized. All of them are doing very well, and I've never heard any complaints coming from their direction.
Most of them belong to the Mason Union or Ironworkers union. Several have retired very well. Most others have been members for 15+ years. After listening to most of them talk over the years, they are in it to make as much as they can as fast as they can. They are looking out for #1. If and/or when unions are a thing of the past, they will deal with that if/when that time comes. Until then, they are getting their piece of the pie. I've often considered moving up north to do the very same thing, but I hate it up there.
I have no personal experience, so I can only speak of what I hear and read. I can see both sides, but with the events going on these days, it's not looking very good for many of the unions.