I think that’s overly simplistic.
Personally I support all of those that have downed tools so far and think that they all have good reasons for going out.
There are good arguments against some of the action as well.
Not all the strikes have the same context.
The Scottish teachers’ strike was different from the English one because of the budget constraints on Holyrood. There were reasonable arguments put forward about the distributional impacts of that claim on lower paid staff. Of course, it’s P&B so there was some knee jerk reactionary Ill thought out shit too, but there was at least a point to make. We had a teacher on here saying he’d voted against action (in England) because he’d prefer funds to go to lower paid assistants. That doesn’t fit your categories at all.
There’s also a moral hazard problem. In my Union days (in a small Union) we balloted on and went on strike against the committee’s advice. Their view was that there was no appetite in the membership for prolonged action (true) and any effort would be tokenism. We had such low density in the workplace that no one really noticed we were out for a day and the employer pushed through the changes anyway.
Obviously it’s not exactly the same for the bigger unions with higher membership densities but showing your hand can be a bad idea and let the employer know just how weak your resolve is.
Then there’s the problem of the occasional grandstanding egomaniac who likes calling strikes to get on the telly and be all Scargilly without any care for their members long term best interests and the sustainability of their position. I don’t think there’s as many of these as there used to be, but there’s a couple.