Wasn't this the same track the Alonso/Massa incident happened back when it was actually questionable within the rules? Now that it's not, I can only assume they were worried about the optics.

Hamilton defended really well when Bottas attacked right after the safety car, it's hard to say what might have happened if he had gotten past, they made it seem like the communication came in the stadium section. Bottas is pretty unfortunate to not be more in the title fight, but it's so tight at the top at this point those points will matter. He does feel like he's owed a win this season though.