There will be no repeated mistakes that Real Madrid will make in this transfer season because we can see that Real Madrid have acquired several young players at not too high a price and left money to take Kylian Mbappe when the time comes.
Many hope that Kylian Mbappe can be present among other players at Real Madrid to be able to take his glory in the champions league later.
Nasser Al khalifi will not let Mbappe move to Real Madrid for free. He had spoken and wasn't happy about the decision of the player to not extend his contract and activate the 1 year renewal option. This put PSG administration in an awkward position and all of them will be convinced that his departure this season is essential for the team since they are the only one losing in this whole story.
Mbappe have a good salary. Real Madrid will get the player for free next season. PSG will lose him once for all for free and this isn't good for them. They will make him move for a good price by the end of this transfer window!
I also think Mbappe won't be able to move to Madrid this season because it would be huge money for the club. Real Madrid won't pay that when next season they can buy Mbappe at a reasonable price. I think nothing serious will happen if Mbappe doesn't play for Real this season, although they will miss such a striker.