Its useful for me, and surely this or any sample size of 1 undermine your point as otherwise your point is unfalsifiable.

I am familiar with a key difference here:

Some people find nihilism to be demotivating

Some people do not

For me, it helps me remember to try to recognize my privileges, support systems and luck. I respect people that play the cards they are dealt. Any child prodigy with a lot of resources could just as easily done nothing with them, so the nihilistic approach more so helps me not resent people that won a birth lottery and also appreciate what I do before I forget and start giving generic success advice.