For now, Luis Enrique is calm a little because the difference in points with second place is quite far so that PSG can focus a little on the Champions League match. Luis Enrique can rotate his players and keep important players like Mbappe to use in the Champions League match. And that can save stamina PSG players can compete strongly with other fierce rivals. In the second leg PSG will only have to play a defensive strategy so that Real Sociedad will have difficulty creating goal opportunities because PSG has locked the aggregate 2-0, even if PSG loses with a score of 1:0 PSG can still qualify for next round and succeed eliminated Real Sociedad in this round.
Yes, I agree with your opinion that Enrique should be smarter in rotating PSG players to maintain his position in League 1 and also be able to qualify for the next round in the Champions League and the 10 point difference from Brest should give Enrique a sense of comfort in keeping important players. like Mbappe who should be kept in the first half and will be used in the second half of every League 1 match to maintain his physical condition so he doesn't get tired when competing in the Champions League.
It seems like this method will work well if Enrique is really smart in managing his players but it seems like Mbappe doesn't want him to appear in the second half because he wants to continue making new history by scoring big scores and I have concerns if he is too enthusiastic about scoring in league 1 it actually has negative impacts such as injuries which will have a negative impact on Mbappe's future.
For the Champions League match, I won't worry because PSG will clearly beat Real Sociedad, even though they will be playing away from home, it seems like Mbappe is still capable of providing an even bigger aggregate score.