> Term limits would fix it

This is really obviously not true. The Democrats' preferred candidate for Maine's US Senate seat, Janet Mills, was 78 years old. She had never served in congress. (she dropped out of the primary when her impending loss became obvious)

Demographics in most developed countries make catering to old people the strategy to win elections.

Term limits are perhaps the dumbest idea that ever plagued democracy. The idea of mandatory firing your most qualified, experienced employees in an incredibly difficult job that can only be learned with on-the-job experience is literally insane. If not for term limits, the US would have had Obama in the presidency this entire time instead of the absolute garbage scraps that were left over when they fired the only person remotely competent enough to lead them.