At least, I don't think in any of the places I have travelled lately. Of course, just because it isn't permitted doesn't mean that people aren't going to smoke in the room, but for those who will smoke in a room anyway, is the sign going to stop them?
Humans are very hard to control, and most people believe laws are made to be broken, sadly.
People also know exactly what they are doing, they just choose to do whatever pleases them.
Everyone wants to do what they want, but want others controlled.