"In Riot’s latest /dev post, it was mentioned that there was a discussion about whether an ARAM-level rework would be able to salvage Twisted Treeline, but the difficult decision was made to shut it off at the conclusion of the season. Citing the lack of growth, it’s an unfortunate but reasoned decision. There simply weren’t enough players to sustain it, with numbers dropping below that of the second Nexus Blitz run. " (Source DotEsports)
Look. I am not going to pretend that I was some huge proponent of Twisted Treeline. I thought it was neat, and dabbled in it every once in a while, but I never got too serious about it. But this. This bothers me. You cannot, CANNOT point at Twisted Treeline and say "Well, it wasn't growing a playerbase, so there was really nothing else we could do but decide to shut it down", ESPECIALLY when you did practically NOTHING to save it. Yeah, there was the odd balance patch for it here and there, but Summoner's Rift gets patched EVERY TWO WEEKS. You cannot expect me to believe, or anyone else for that matter, to believe that Twisted Treeline rotting was not a result of negligence.
You did NOTHING with it. You threw balance changes at it. You didn't do any events around it other than TT Hexakill, which was NOTORIOUS for having one team snowball while the other took upwards of 7-9 minutes just to get to level 6. Even during Halloween, during the Harrowing, TT felt like an afterthought.
One or two big changes to Twisted Treeline is not going to be enough to grow or sustain a playerbase. Your main focus has always been on Summoner's Rift, and we don't even need to get into the extremely toxic mess that is the fanbase for THAT game mode. Choosing to kill Twisted Treeline is a mistake, and It will be costly. Of that I am sure.