Unions are fine ... I've never been a fan of the public unions though, since they demand outrageous salaries and benefits in Ontario. We have a teacher's strikes, transit workers get so many breaks it damages public transit efficiency, postal strikes, and it's not like they're underpaid or in poor working conditions.
Depending on the systems, wages eat 70-85% of operation cost, leaving very little for other things or quality of service. In some cases, operation cost has an impact on the construct budget that it may cause projects to be defer.
With automated trains coming down the road very fast, operation cost will start to fall once drivers are remove and replace with a less pay person on standby incase they have to step in and remove over time. they cause what fare riders have to pay as well those maintaining the equipment.
An 18 km line in Germany is seeing non drivers on an S Bond line trains. There is an railroad running 200 plus car long long distance non man. BN has already done some long distance trail testing with non man trains.
Have work in both sectors, non union was the best route as you can pay x worker more over y as they are doing more and the quality of work is better. When x slacker join a group of works in a union and those workers that were better workers before the slacker join, their work starts to fall as they say why so I do more when x is getting the same pay while doing less work. A lot harder to fire a worker or discipline them to the point companies give up unless it real bad. Seen this as a worker and on the management side. Paying people a fair wage is very important, but what does that mean to people is a different story.
In time, this line will see no divers at all.