[pixelmonkey]

This was covered well in a PBS Frontline documentary, "The Pension Gamble":

https://www.pbs.org/wgbh/frontline/documentary/the-pension-g...

And also in their followup, "The Retirement Gamble":

https://www.pbs.org/wgbh/frontline/documentary/retirement-ga...

Both can also be found on YouTube.

I rewatched both just a few months ago, to understand the history a bit better. The short answer is that eliminating pensions was part of a larger restructuring in corporate America, wherein major companies that became megacaps in the 20th century used the Chapter 11 bankruptcy rules as a shield to eliminate employee pensions, while the burgeoning consumer finance industry of the 1980s and 1990s was all too eager to create a new fee-generating monster in the form of 401ks.

These days, employer-matched 401ks with low-fee index funds are the only sane retirement tool available to middle-class workers, but much like US employer-sponsored healthcare, the system is about 10x more complex and 10x more precarious than it otherwise could be, and it benefits all sorts of ridiculous middleman paper-pushing rent-seeking corporations along the way. The news from IBM is ironic because employees will rightly revolt against this "pension" because now that Vanguard-style low fee funds have become ascendant in 401k accounts, a number of new unscrupulous financial actors are pitching "pension plans" to companies which are really opaque fee- and cash-grabs for employee retirement accounts.