What Robosprog mentioned about Target Audience is spot on.
Maybe that would answer the passive reasoning of acquaintances whom of which refrain from mentioning Pewdiepie and/or his video contents. Maybe most of us have moved on.
But that point about unsubscribing because you haven't gotten around to it could also be true too. I sub and actively look for new episodes of Game Theory on YouTube and nothing else really (sorry AGP D: ). If I recall, I am still subbed to Pewdie despite not watching any of his videos since I stumbled across Markiplier. That must have been around three years ago.
While I doubt that people in a similar boat to me are abundant in relation to Pewdiepie's current subscriber base, it tends to consider how many active subscribers he has - let alone, what defines an active subscriber.
I cannot hate Pewdie though. I really have to compliment his propaganda techniques, target audience immersion and his charity work. Like most Youtubers, whom of which start off at nothing, he has come a long way and done very well doing so. I just prefer to watch someone else, as that both entertains me more and I relate more to such comedy.