I mean, just on the physical front one is not able to do things they used to and require more medical attention. That brings with it financial costs, dealing with broken systems, etc.
Of course again the trend is that many people don't exert said self-care and fall subject to ailments much earlier (or just have bad luck w/ a host of varying types of environmental/genetic circumstances), and just generally use getting older as an excuse to withhold themselves from a great many things. This again is not destiny, merely a trendline that can be changed.