No, it's not implicit. Why is your football analogy reasonable at all? There is also the matter of the general pattern of conduct that president Trump has established over the last few months, which is more relevant here. If you tell people that the election is being stolen and as patriotic Americans they ought to do something about it, as he has been doing, and you keep saying that for quite a while, you then lose the claim that there is an implicit "despite" in anything you say, especially since the call to civility is such a small part of the tweet. If you look at all the other things he's said the calls to civility are also quite small and token there too. Like most people, if he wanted to say it he's quite capable of saying it properly. So it's not implicit, it's just a rhetorical tactic he uses.