I support pensions, but this has to be done at the federal level, and funded heavily through taxes and pro-natalist policies to keep demographics correct. Cities, states, counties and companies are not able to adequately fund defined benefit pensions.
Luckily, most Americans have pensions outside Social Security, so you won't end up in a situation where nobody has a pension if it collapsed. It would still be bad, but not as bad as if the federal government had a pension monopoly.
If I was a pension rep or director for the cops, teachers, firefighters, or whatever, best believe I would maximize my members' benefits to the maximum extent the law and guidelines allowed. That's really all that is happening with these unions. Sure, there is some corruption going on (when isn't there in any large organization, much less government agencies) that isn't helping matters, and there are idiots that are making things worse. But these issues are in the seriously tiny minority of the real problem: People who could not do math properly or were corrupt from the get-go set up an insane pyramid scheme built on ridiculous population growth and capital appreciation models, and no one wanted to stop the music for decades on end.
The most likely scenario by a WIDE margin is that pensioners are wiped out or forcibly restructured in a court of law, getting a small reduced fraction of their promised ("guaranteed") benefit. It just is. In America, we don't fix gradual issues - there is simply no incentive to do so. We ignore them until they blow up and then we do something about it. This sounds stupid, but it's perfectly rational on an individual level.
That probably depends on the culture.
My experience from Finland is that there is always a pension reform going on, or at least people are planning the next reform. It's been recognized for decades that the pension system is unsustainable, and reforms have gradually made it more sustainable. Pension growth is now based on a mix of price and wage growth, the initial pension is based on lifetime contributions rather than final wages, retirement age automatically follows changes in life expectancy, and so on.
Older generations certainly got a better deal, and young people are always cynical. But as people age, they tend to gain confidence in the system, as they have seen it change over their careers.
Quite a bit of my university work in the early 2000s revolved around studying and modeling pension-type retirement plans, primarily in the United States (Chicago and Philadelphia mostly come to mind), but a little in foreign countries. While EU pensions tend to be in worse positions, it's a distinction without a difference: Pension reform is basically impossible. Catastrophic bankruptcy and refusal to pay benefits is coming to a theatre near you, because the political will to even begin meager cuts (and so-called "drastic" cuts are indeed merely meager) does not exist.
Politicians who propose meaningful cuts to pensions are guaranteed a single term in office while the candidates waiting in line promise to keep the Ponzi scheme going.