“Rules of the game” haven’t changed. GOP and trump have rejected prior norms and are playing by the rules.
Obama received deference early on because in both his words and actions he reached out to republicans and tried to be a unifier. The trump we have seen so far has only said word about reaching out and unifying people, but his actions are the opposite. His cabinet choices are controversial and divisive, and his rhetoric has been divisive and bitter.
So far trump has shown he doesn’t play by the rules, and because of that he doesn’t deserve the “norms” that playing by the rules affords.