There have been many improvements in coaching, tactics and Football in general since when Mourinho last coach Real Madrid in 2013, he can still win some trophies for Madrid though but you cannot compare to when he was at Madrid before and expect much from him.
Under Xabi Alonso, Real Madrid started the season well but they got issues with last of consistency and lost the Supercopa final to Barcelona and he got sacked after the game and Real Madrid need an immediate result after going trophyless again, that is why they signed Mourinho, so if his performance with this squad is not up to that standard to be able to win trophies this season, then you can not expect them to have patience with him.
When Mourinho left the team was still performing well but struggled for a few years after Ronaldo left and then when Ancellotti left too they haven't been the same ever since that's why they had to bring Mourinho back to the team. Of course he can win trophies again, he might be older now but still capable of turning things around for them. Real Madrid has not been performing well so much is expected from him. With the players signed and quality of the team i expect a much better performance, I expect trophies and I have believe that Mourinho is the right person to give them all this. The major issue was the ego between players and I am sure he'll fix that in no time.
This season's champion league cannot be for PSG anymore. I know those guys are now used to winning because they have won so many tittles together. They have much believe in the team that they aren't scared of any team. The coach is really doing a great job at that club.
However, I don't see them winning the champions league next season. I don't even think they will qualify to semi final, and anything that makes them not to reach the Semi fina, I see Arsenal lifting it. I am not saying this because I am a lover of Arsenal, I am saying this out of the hunger in the Arsenal team. They are so hungry for the champions league tittle after lifting the premier league. They have places it as their next target, I think they will be able to achieve it, they only thing they really have to do is to strengthen their front line, because as it stands, they don't have a skilful player upfront, the likes of Gyokeres and Herverts is unable to do anything there. They need a sharp attacher and a very skillful left winger that can take on defenders anytime. If this can be accomplished, then, I see them winning the league and the champions league again.