As a colorblind user I'm not quite sure what color the send+mic button is, but I'm drawn to it much more strongly than the normal send button. At the very least you'd think they would have had a pop-up confirmation message...
It doesn't seem like Google tested this on many real-world users before deploying...?
A UI that requires the user to read every button and look at every icon that they click on because it may have been changed to do something completely different is a terrible UI.
While I might notice a new color, I'm not certain that I would.
Furthermore, the icon doesn't have anything for you to read, since it uses an image (whose meaning may still not be clear to an older or disabled person; it kind of looks like an ice cream cone to me).
Then again, I don't watch TV so maybe I missed out on it being used.
In doing usability design even for astronauts or pilots I don't think you could fully trust a user to behave as you describe.