Around 2014, I got into Game Grumps. And had been really into it for a couple of years until I fell of because I felt like it got stale and boring (or I grew up, I don't know).
Most likely the first option, but a bit of the second. His content got boring for me only after 4 months. What does not help is Arin got weird and contrarian opinion, and does not know what he's talking about when it comes to game design. That and he put out too many videos that cluttered my subscription feed.