Their whole punishment for cheating is the disqualification of a qualifier. There's no way the players were unaware of it. For what they did, I would have expected at least a six-month suspension.
That’s a slippery slope. I’m sure people have evidence of other teams doing the same thing. If riot decided to ban T1 you never know what will come crawling out of the woodwork and how many teams would get banned.
Many notable pros have come out saying these sorts of things are common. It would be better for riot to address the issue with rule changes or tweaks to the tournament clients. Why should coaches even be able to use chat functions during a match?