I don’t have anything empirical, but I’ve come to the conclusion that this mostly depends on the replay value of said game.
YouTubers might hinder story-based games, should they do full playthroughs and so spoil their audience. I’ve seen some publishers explicitly request them to not finish any let’s play, or they set a hard line. Something like this was done by the devs of At Dead of Night.
EDIT: I don’t mean to imply story-based games have zero replayability. One could have branching paths, alternate dialogue, easter eggs, yada-yada.