Hewitt don't forget the walking dead, IMO he did the best let's play of it, he loves the games that have a plot behind it, if not he will act stupidly for the sake of the other part of the fandom that love those kind of things.
I dont know about the walking dead, because i had already abandoned pewds at that point, but what you're claiming is simply not true. If he loves games with good plot, why was he acting like his psychotic ear-screeching, self-loathing self in games like Calm Time, Fibrillation, Ib, and Limbo.
I haven't seen the WD playthrough so I can't really comment, but my argument still stands: he has way more repetitive shit than anyone and I've grown tired of his style; if a game requires lots of text and the story is deeply symbolic, he just doesn't give a shit and plows through, often leaving me go "wait, whats the plot? Why is that thing that happened, happened?" What I do know is that the walking dead game from telltale is braindead easy, or at least easier than pewd's usual share of game libraries. Plus, its a pretty famous franchise. I'd gather he only decided to play it because every LP-er was and will.
But this is just me talking I guess. I look at Markiplier now and to me he is ten times better than pewds. He appreciates the games he plays instead of just playing it because he has to, tells the watchers of his vids things he notices and how the game is so we can appreciate it with him, and his jokes are funny and not loud. He cuts the game playing time appropriately, so we don't have to slog through every mess he makes in a way that doesn't border cheating. And he is also pretty charitable. Basically, these are the benchmarks that I now recognize as what an LP-er horror or otherwise should be. And if Pewds doesn't change into that then I've lost all faith.