As someone who is on board with people using communication tools:
Do you think people who would not say "I don't like where this is going" would be willing to tap the traffic lights? It's basically still you saying "I don't like where this is going", still in full view of everyone. I'm honestly not sure how the communication tools help with speaking up, besides providing a few predefined options for you ("yellow light means this, red means this") instead of you having to find the words to explain how uncomfortable you are and what you want the solution to be. I'm not trying to tear them down, I'm just honestly curious.
Might as well out myself and say I've never personally needed to use these. But I don't have to fully comprehend them to support other people doing what makes things healthier and easier for themselves, hence my not understanding while still supporting people using it.