Honestly, in the grand scheme of things aren't most people pretty useless? I'm comfortable being pretty much useless. I go to work, come home, spend money, eat, sleep, repeat.

I have no illusions that I'm particularly useful or contributing anything to the world and just plan on passing the time until I die.

I think it's funny that more people can't accept the truth about themselves. It's not a bad thing being useless, it's just reality for a huge number of people, myself included.

"Fear of uselessness" seems to be a euphemism for the fear of dying, both the process and the ending.

I'm not sure there is a great answer here, so I'm just going to post the Alan Watts talk that brings some perspective for me.

Alan Watts - Music and life: https://www.youtube.com/watch?v=ERbvKrH-GC4

"[..] but we miss the point the whole way along, it was a musical thing. You were supposed to sing or dance while the music was being played".

simple he needs a hobby he has a passion for, took my dad years of contracting after retiring to realize he could be happy with his wood working hobby, oh and traveling.

it isn't so much not being useful but being idle with nothing to do which isn't the same thing

This sounds to me like a disappearing problem. Increasingly, people do not need an employer to be useful. Technology enables an individual to accomplish amazing things of great value with minimal cost. When a software engineer retires, what would prevent him from continuing to be a useful member of a software team? A software team is only handicapped by the presence of a centralized corporate structure that requires the team to live in the same geographic area, to be productive enough and lowly paid enough to compensate for the monumental inefficiency of maintaining an office building, multiple layers of management, open floor plan offices in spite of mountains of research showing how detrimental it is to productivity, retention of a 40 hour work week even when 40 hours of productive knowledge work is neither possible nor necessary, etc.