Supposedly, Trump promised to never touch Social Security and Medicare, while Romney was tied to Ryan and attacked a lot for potentially cutting Social Security and Medicare. Yet Romney seemed to have gotten a higher percentage of seniors than Trump.
This is not actually a particularly effective attack on a Republican candidate. Anyway, my guess is that criticisms along the lines of 'norms and values' are more resonant for seniors, who have observed American politics for longer and might have keener senses of what the norms exactly are, and are likelier to perceive the ways in which Trump is a departure from those norms.