Earlier quoted context omitted.
Generally the number of your friends who have funerals is heavily biased towards the end of your life. America's average lifespan is 77. When you're 16, your parents are perhaps 46, and their parents are maybe 76. And a lot of people live for 10+ years after retirement, so your teachers might all be alive too. If you've got a big extended family, or you're part of an organisation like a church where 16 year olds come…
Your grandparents also have siblings, and your parents would drag you to those funerals. You should also have people of many different ages in your social group and some of them will die of old age (and once in a while someone young).
"Should" seems right, but in practice, do young people have this? How? (Thinking of the US here.)
When I was a kid, this came through church. But church attendance among the young has fallen off a cliff, with (to my knowledge) no replacement.