I was a lowly peon in a health insurance company for years, and this is a big thing as you age or circumstances change: checking that the policy meets your needs, and is right for you.
The plan that was perfect when you were young, with a family, and years of medical problems ahead of you may be a total waste now.
X coverage for dependents (the spouse and children plan) Including the pregnancy, etc. care.
X wage-replacement coverage if you are disabled from work.
Glasses and dental? Probably still useful, unless you're blind. You may still want your dentures re-lined, and even if your teeth are perfect, there's that unexpected fall.
If you're 95 and your health is good, yeah, probably less coverage, although things do happen - although,
not being in the US, you may have some sort of government medical? Check that out and see what duplication there is. (I am in Canada, anything that happens in a hospital is covered.)
Although, I don't entirely blame your father - most people never periodically check their coverage. And, when your dad started out, it was probably a point of pride to be able to get the 'best' coverage for his family.