Maybe it isn’t about caring for them maybe it’s about teaching them to live with what they have. The skills for being retired are different than the skills of working. The skills of taking care of grandchildren are different than children.
We just sorta assume people know what to do when they get a certain age and maybe that isn’t a valid assumption. I am just thinking of an uncle I had whose health just crashed right after he stopped working. He didn’t add physical or mental work to make up for not working anymore. As opposed to some elderly I know who have loaded up the hobbies.