Of course not, but it is not only about the goals, but also about the significance he brings in for the team and that is insufficient at the moment. And while you are saying that it doesn't mean he has to score every single game he plays, I think that the Real Madrid fans were indeed hoping that Mbappe will become the next Ronaldo.
But in my opinion he has been in decline recently. Maybe he realized that Ligue 1 isn't La Liga, but then again he has played dozens and dozens of Champions League games and World Cup games and he should know what to do. If you ask me, I think his start in Madrid was not what he himself was hoping for and as I said, it is not only about the number of goals.
Even though we all say it is not about the goals but it is certainly the only yard stick I see here that people are using to judge him, overall he has been doing just fine and the only expectations he has been short of is challenging for the top scorer Title with the likes of Lewandowski. If he had gotten that goals I doubt anyone will be saying he is on a decline, Real Madrid team thought that signing Mbappe will make them invincible and they would be higher on the table but not everyone get it that he is a player that needs time just like everyone.
Even if Mbappe already have experience from other clubs I think he need time just like anyone, Messi went to PSG and he had the worst first season there, if the greatest of all time could face such challenges then Mbappe is also not going to run a way from it either