They're using the leverage they have which is exactly what unions are for. They can't, for example, lobby effectively for UBI or universal healthcare. So they do the next best thing.
If these people, or any people, thought for a second that automation would make their lives and the lives of their families better they would be for it. If you want progress people will need to be a part of it, not a victim of it.
Unions have limited leverage, using it to stop automation is like fighting the tide. They should be arguing for training for positions running the automated cranes, priority in hiring for new positions, job placement assistance, tuition reimbursement, or other things to help employees.
Well if you don't realize in today's world you are either useful in a way dictated by vastly wealther people or you starve. So in a world with literally zero global compassion (meaning those in power who are in charge of keeping us safe) will cast you aside for an extra buck. If automation and innovation ment the emancipation of all humans to chase their passions, yes I'm all for it. But it's not. The change is to fire the workers to increase profits. That doesn't help anybody.
That's what they said 100 years ago and it got a little bit better but it's far worse than even those people would have thought. If you think those in power won't drive everyone of a cliff to make a buck you are in for a surprise. Wealthy people are literally planning to escape earth over giving up any money or power. I'm not doom spiraling I just want more people to wake up and stand up for their fellow humans before it's too late.
Fully depends on the way automation is done. But mostly it is to drive wages down and leave the employees left in less safe conditions and doing the very hard jobs which are hard to or cannot be automated wearing them out faster. Just as supporting roles get more pressure with also less means to succeed in their jobs and more stress.