The benefit is worth $2000 a month. See, for instance, LACERS (City of Los Angeles) which offers 25-year retirees over $1,800 a month in dental and medical subsidy. It’s shown on the retirement plan balance sheet as OPEB (Other Post Employment Benefits) and is rarely ever funded close to what the regular pension system is. https://www.lacers.org/aboutlacers/publications-forms/publications/retired/open-enrollment-guides-brochures/2018%20Health%20Benefits%20Guide.pdf
Some agencies make you retire immediately to claim the subsidy; if you don’t take the retirement payout (maybe you are going to the private sector or want to wait a few years to spike the percentage if you feel you have a long life expectancy) then you get zero. The State of California is that way - work 20 years and get free coverage for life and that of your family BUT you have to retire, and you can’t do so until 50. If you work 20 years for the state, go to another state or the private sector, and retire from there, you get nothing towards retiree health care. https://www.calpers.ca.gov/docs/forms-publications/state-health-guide.pdf
Quirks like these are why many people argue pensions are unsustainable. If someone retirees at 50 but prior to doing so marries someone half their age, that person could inherit a pension and retiree health care for their life. Let’s say the happy couple has a few kids, and they are covered until 26. Conceivably 25 years of public service could lead to 45 years of family coverage being paid out. This is in addition to the known loophole in some plans that don’t prorate based on spouse age but pay out a survivor allowance to the spouse regardless of age. In the era before same sex marriage it was not uncommon for a lesbian or gay person to “marry” a close friend’s child prior to retirement, to transmit a lifetime of benefits to them and their children.