With Cavani Uruguay would/will have a chance, still not a huge one. It's just that France is too good. Griezmann isn't any worse than Cavani, and even though you can hardly put anyone on Suarez's level, there is a whole slew of French players that are immeasurably better than the corresponding Uruguay squad. Then there is Mbappe...
As for Brazil, sorry to disappoint: they will go out with thunder tomorrow - may not be quite as bad as 4 years ago, but still. Brazil is out! And if it's not, then lets recognize one and the only player who is capable of making that happen - Philippe Coutinho!