Heavy defeats like this opens up eye of the coach to see places the team has lapses. Real thought they were ok and needed no further signings because they thought they have covered up all areas and it seemed so as the won all their games in the CWC except for the opening game which was a draw. The PSG game showed them that they still had lapses to fill and this has made the club to realise that they don't have a proper 10 and a standing DM, they still lack the fluidity of a CB and a LB, this game opened this up and if they fail to address it, they will only excel with the likes of small teams and suffer whenever they meet a big team.
Yes, Vini and Mbappe has a problem we could see that in the PSG game also.
I can understand wanting new players, but another midfield? That makes absolutely no sense at all considering how many midfields they have. They have Jude, Valverde, Camavinga, Tchouameni, Arda, these are all midfield players and you can't even play all of them at the same time, so you have to already bench some of them.
And getting Mcallister wouldn't make them suddenly that much better. They were looking to get Davies from Bayern for left back, but they failed to convince him and Bayern, so that would have been better without a doubt, but it is not really that complicated at the moment, just go find someone else. I am sure there must be a lot of great left backs out there that are on sale for the right price and real should go get one.