I'm somewhere in the middle of this.
My main bike is aluminium. Given the amount of miles I ride, it is almost certain to outlive me. So I can reasonably ignore fatigue problems.
I got it for free, so I've nothing but time and upgrades invested in it. They are "upgrades" becuase I've chosen to make it match my ability, not because there was anything wrong with it as-was.
But, like
@SkipdiverJohn , I expect this to last well, and don't expect to forever have new machines. Which is out of my reach financially now and forever anyhow.
Old cyclists do die, but quite often, their bikes don't...