Talk to people on their deathbeds and you'll notice that they talk more about relationships than activities.
The older I get, the more I understand what they were saying.
However, one time it occured to me that maybe a dying person's regrets are not the way you should live your life. They didn't get infinite wisdom just because they're dying, and also the point of life is not that to be happy about your life and choices in your last couple of hours/days.
I'm not saying you should dismiss everything they say, but to take it for what it is: the thoughts of a mind heavily influenced by dying.
Its not about being satisfied or not with your choices on your deathbed, so much as realizing on your deathbed that you've been miserable due to how you've lived, and have been too preoccupied or angry or fearful to pay any heed and make changes while you still had the chance.
The first bout one has with this is when someone you know well dies, and you find yourself thinking about what could have been said or done but cannot now. That's probably also why the realization generally doesn't happen until later in life...
"The peak–end rule is a psychological heuristic in which people judge an experience largely based on how they felt at its peak (i.e., its most intense point) and at its end, rather than based on the total sum or average of every moment of the experience."
30 years ago, I would have been quite puzzled by your explanation. Today, it seems so natural.