I think at it's core this is deeply rooted in a fear of death/disability
People offer unhelpful platitudes because deep down they know that they can also one day get some kind of diagnoses for an illness. Cancer, dementia, alzheimers, you name it.
It's coming for all of us.
So when they ask "did you try x????" It's them really saying "god please let miracle cures still exist, I can't handle confronting my own mortality"
And if you go "no, I havent tried that yet", they get to smile and proceed in life, "oh well if I was sick, I'd try everything!"
Which is pretty much all that seperates them, for now, from acknowledging the void they just brushed up against.
Some people would rather very carefully arrange a thin sheet covering the giant black pit in the middle of their living room, so they never have to look at it.