@Riot - Don't Remove Teambuilder Yet!
I'll start by saying that I have not played many teambuilder matches. However, I think it's honestly really good.
According to your article, teambuilder didn't serve the purpose you intended--to allow for certain team comps to be made. I agree that teambuilder didn't achieve this at all, but it did do something else for the playerbase: it allowed you to be assured of playing a specific champion in a specific role.
Other than teambuilder there is only 1 other way to do that, by instalocking and being stubborn, which is not fun for anyone else. While teambuilder might not do what you want it to do, it certainly isn't a bad thing, so there isn't a reason to disable it.
IMO, teambuilder should stay forever unless it gets severely outclassed with the Normals new champion select whenever that comes out. I would also be ok if teambuilder stayed for now but was disabled automatically once the normals new champ select came out.
Without teambuilder, there would be no (non-toxic) way to be assured of a champion and role. With teambuilder, well, nothing bad happens, so why disable it?
That's just my opinion though, and perhaps it is wrong--as I said, I don't use teambuilder that much. What do you all think?