Real Madrid definitely had some luck last year. I just think it's a bit silly to say they "somehow went through." We know how they went through: by scoring more goals than the opposition.
These were not close ties where Real Madrid's opponents somehow failed to score after getting a million chances. Real Madrid were punished for defensive mistakes, and then had to go score goals in order to make up for it, which they did.
City scored 5 goals in two matches against us last season. Yeah, they missed a few goals. But 5 goals should see you through a CL semifinal. If you concede 6 goals and go out, then sorry, I'm not going to accept that you had some kind of great performance.