Mort Sahl co-hosted the 1959 Oscars but was left off (or so I've been told) from the memorial. WTF?
You, dear human, should remember that humans forget very very quickly. The brain cells of of a Zeitgeist are made up of the actual brains of humans living that milieu. Every time someone dies, the culture loses a little bit of memory. Someone new is born and starts forming memories, a new neural connection, a new store of new memories. The brain doesn't notice when a brain cell is lost.
The average age in the U.S. is around 38.5 years. Sahl was before the time of these people.
The average person didn't forget him, as they never knew him. It is only the hive mind that forgets, and that is because its memory is always dying.
You are basically a single cell trying to scream through the clutter, but the hive-herd has moved on. The hive mind is not the wisdom all human history, but the collective mediocrity of an age
(what else is an average, after all, than the mathematical distillation of the mundane?). The Zeitgeist is a thirty-something creature which believes it "knows it all." And so long as the human race continues, it continues, evergreen and ever-dumb. The only immortal sentient creature on earth is a schlub.
If you want to be remembered, common formulas are
be infamous (Hitler),
die young (Monroe),
become an ironic joke caricature of yourself (Shatner), or
plaster your name everywhere in the vain attempt to be remembered as important (Trump).
In the end, however, we will all be forgotten ("Behold my works ye mighty and despair"). It's not how long you live, but the lives you touch along the way. This person touched yours, so that is a sign of a life well-lived.