You can’t cut the pension for the retired, or the soon to be retired. Instead you try buy outs and phase them out. New workers get 401ks. Old workers get pensions. Middle aged workers get a choice.
30 years later, the pension holders are dead, or your company is. Either way, it’s no longer a problem.
The feds went through this back in the 80s when they switched from CSRA to FERS+thrift (basically a 401k). I think that helped but didn’t completely solve the problem. But at least they are more solvent than Chicago.
30 years later, the pension holders are dead, or your company is. Either way, it’s no longer a problem.