If Mbappe had scored that penalty in yesterday's game, it might have been a different story today. It's possible that Real Madrid players would have put in more effort, as that goal could have brought them happiness and boosted their strength. They might have started aiming for a win. However, since Mbappe missed the penalty, I believe it partly affected the players' morale.
We know Real Madrid well they have the ability to equalize whenever they are losing to an opponent. They especially try to win games in the Champions League competition, as they have proven time and again. Yesterday's match might not have led to a win for them, but it's possible it could have ended in a draw if Mbappe had scored the penalty.
I agree with you, that penalty was suppose to be the game changer and if Mbappe had made it 1-1 I believe Liverpool won't have gotten that second goal because the defense line of Madrid would be more stronger and Liverpool would have been the ones to be under pressure but since Mbappe lost that opportunity of making it 1-1 it gave Liverpool the morale to continue pushing forward. Madrid would have gotten something out from that game but killing the spirit of the other players is what caused the whole thing for the Whites not to fight back.
The more Mbappe try to play as if he's still at PSG the more he loses possession of the ball and with all these, Ancelotti will still include him to be among the squad against Getafe. I still prefer Joselu to Mbappe, the Spanish player is more better than Mbappe as the number 9 man, just that Madrid thinks things with the former PSG man would turn out to be positive for them but no, things are getting worse.