I think h6 is VERY dangerous for black from that position, white will most likely capture on f7 gaining a half open g file in which blacks king is on also note white has a pair of rooks on his back rank that would cause the black king to be very uncomfortable hiding behind that weak g pawn. Nakamura is a very skilled grand master, he did the best he could but carlsen got the best of him, h6 would not have saved him

well I don't know if I would dare to try it if I played against Nakamura, but after 22...-h6, why not go directly for the throat with 23.B*h6-g*h6 24.g*h7+

Getting that g file wide open (or just winning a pawn if he refuses the sacrifice), should definitely help us boost the attack

Um... 24. gxh7+ doesn't work if the pawn is no longer there. Do you mean gxf7+?

According to computers, this is indeed a blunder (with the move 22...h6 preferred).  To my unassisted eye though 22...fxg6 really does seem like the way to go.

yeah I meant f*g7+, sorry

But as I look into it maybe the king can escape after that, i don't know

g*f7+, sorryyyyy

Yes, even my computer prefers 22...h6 over Nakamura's 22...fxg6.