About the negative tactics, my main problems are that some people refuses to admit that we're using them, in the first place. And secondly, I don't think this bunch of players have the attributes to excel at playing that kind of passive football. Even against mediocre opposition, we could be playing well last season and after scoring we conceded the ball and part of the field, and then the cracks appeared. We ended up suffering unnecessarily many times instead of keeping the same rhythm an ambition as before.
To play this way we need more mature players with better positional intelligence. For me it's not a surprise that Matic (even without training so much with us) was excellent against Real while people like Lingard, Pogba, Lindelof and some others were lost in the forest. With Pogba it's just a classic in these situations. Even if we leave the aesthetics and 'traditions' aside, I don't think this way of playing benefits this group of players.
We reach a point sometimes where we are simply unable to cross the midfield, and all we do is to concede waves of attacks. Against Real it happened again before the 1-0, and it won't be the last time. I don't expect us to go out there and outplay a team like Real, but between this and being prisoners in our own box there has to be a middle term.
And of course, things like leaving the talent on the bench to play Lingard just encourages the opposition to go forward without fear. Playing quality players and give them a bit of freedom is a good way of defending too, by dissuading the rival team so they don't attack us with all the weapons. I know he's Mourinho and more than probably he won't change a bit, but man, every time I see this team getting into the cave, clearing the ball away and praying to god it makes my blood boil. It's not just something 'ugly' and unpleasant to the eye, I think it's unnecessary and even counterproductive.