Some shows are just paced too slowly, but still provide entertainment or enlightenment. Who are you to care whether a viewer watches such a show at 1.5x speed?
A pile of DVDs became something I had to get through, ditto books, games or albums. Talking to others I found it wasn't just me - that somehow the important thing had been completing things and enjoying them had become almost secondary.
Recently I found myself listening to a podcast at 1.5x speed regularly and after a while it occurred to me that it was because I was resenting the time it was taking up and that the problem wasn't really that it was taking too long, it was that I wasn't really enjoying it but was listening out of obligation (it had popped up in the unplayed list, it must be played!). At that point I said a silent sorry to Mark and Simon and unsubscribed. I've similarly quit watching a bunch of TV shows and I'm far happier abandoning books or games part way through.
Seeing someone talking about watching a movie at 1.5x speed made me think of that - consumption over enjoyment. Yes there are movies and shows that can be watched that fast and still enjoyed but given the sheer volume of stuff out there is that really the best use of an hour and a half even? Surely there was something good enough that it warranted real time viewing?
Maybe it's not the case here but that's what came to mind.
I watch basically all youtube videos at 2x as well (with the html5 player) to the point where I'll actually shut a video off if the only thing offered is the old flash player (and ditto applies to vimeo vids).
However, I've never had enjoyed scripted tv shows at 2x speed, I'll usually dial it back to 1.5x to watch. It's not in an effort to save time, it's that I genuinely find aural mediums better when sped up.