I agree completely it eliminates a huge swathe of people, mostly experienced and older people. FAANG employees, ime, are biased towards childless / single people with privileged backgrounds.
Tree inversion sounds weird when you hear it phrased like that, but in an interview it would be explained with an example (just swap the left and right children recursively).
It also seems to neatly split people into camps who think "this is trivial, and totally reasonable to expect somebody to answer, even if it's a little contrived", vs those who think "this is not practical, and you'd only know the answer if you'd already practiced it, so it's not fair to ask".
> It eliminates competent, skilled people who don't have the time to memorize the latest cargo cult trends in hiring
But given that you already acknowledged that it's pretty trivial, why would memorization be necessary for a competant person?
Uhhhh... It eliminates competent, skilled people who don't have the time to memorize the latest cargo cult trends in hiring. Look in the article for a glaring example.
"Invert a binary tree" is actually considered an easy problem to test your basic knowledge of how trees work and tree traversal.
So would simply printing out a tree, and at least that's something a person might actually do.
Tree "inversion" doesn't even make any sense and at this point I'm convinced that the cargo cult is choosing it because it's the extent of their own understanding of trees and somehow sounds extra technical to them.