One of my mothers friends, who is now in her 80's, has been retired on a pension for over 40 years. She started working for her municipality right out of high school at 18, and worked 25 years as a clerk to get a full pension. Retired at 43(!) with 75% final pay (annually adjusted) and lifelong medical benefits.
Its totally insane and completely unsustainable. Back in the day people usually keeled over at 65 and the US was viewed as having achieved infinite growth forever, so perhaps back then it was a reasonable but generous offer. Today however it's just straight up corruption and waste to offer benefits like that.