The principal problem isn't seniors run amok. It's an economy run aground. The economic stumble is more important. As a byproduct, a faltering economy will precipitate further social security funding problems. Worker demand exceeds worker availability and drives up wages.
Inflation brings increased interest rates.
As the population ages and the birthrate declines, family life will change. Different lifestyles and cultural patterns will evolve. The infrastructure to satisfy the new patterns will be reconfigured. Some industries will be forced to discard surplus production facilities and their economies of scale will diminish, giving an additional stimulus to higher prices. Changing demographics will modify consumer preferences in clothing, housing, entertainment, food, etc.