I have eight accounts, self leveled, that I play on. My friends list on all of them are almost always full of offline players even though I accept almost any add. On this account, my oldest, I can count on one hand how many different players I'll see online in a week. I know that a lot of my friends quit in season 5 during the devourer days, and those that hung on through cinderhulk tank meta, tp/smite top quit after the abomination that was the ardent sensor meta. I highly doubt league is dying, I just believe the older player base is moving on and being taken over by a younger crowd.