Snipe is still insane in TvZ. Ghosts counter spellcasters that don’t really have a counter to ghosts, and then they also counter every other unit, especially the lategame ones. Once you get to the lategame, there’s never a reason to not mass ghosts. The game says that roaches are the counter to ghosts, but has anyone ever made a roach after the 9 minute mark?
Ghosts exist specifically to counter spellcasters and large biological units. Roaches are going to last a lot longer against mass snipe spam or EMP’s than Ultralisks, Brood Lords, Infestors or Vipers.