>>102397624 (OP)Because their streamers stream with consistent, regular schedules, constantly seek novelty and have the acumen to entertain regardless of what they do or play.
There are ENs I like but it's hard to follow any particular EN when their schedules are eclectic and inconsistent, they take frequent long breaks or absences due to "burnout" or "japan trips" and their quality varies wildly depending entirely on whether they like the game or not.
ENs are constantly building sandcastles and kicking them down and the result is that rather than there being large, growing and dedicated viewership for each individual EN, there's just this sort of shared timezone-based audience that watches whatever EN actually bothers to fill the timeslot, but only if the game is interesting and the stream is good and the timing is convenient and there's nobody else on.
Of the ENs, I think basically only IRyS can consistently command an audience that isn't highly subject to what she's streaming and who else is on, and she absolute has been as consistent as any JP in streaming--but her timezone is too late to monopolize a huge swathe of the EN audience.