Retirees who “age in place” a lot of times live in older homes. And with expanded life spans, even second generations are likely to be of retirement age and living in old homes.
A particular risk can be aluminum wiring, which was sometimes installed in the late 1970s and early 80s and then was discontinued because of safety issues.
Wiring becomes unstable over the years, sockets can wear out (and become hot), major fuse circuits can wear out or be from a group known to be deficient, and sometimes new appliances (especially some security systems) can require re-wiring. Here’s the article.