I can remember that a lot of people speculated that inter would carry their performance with Barcelona to the finals, bit unfortunately that wasn't the case. Concerning the Inter's game with Barca, I feel it's just a normal thing for teams to adapt their strategies based on their opponents, and this mostly leads to unexpected outcomes. I don't think the issue was actually Barca's defence mechanism, I just looked at it that Inter Milan knew that Barcelona was a formidable opponent and thus seriously prepared and studied their gameplay thoroughly, and Barcelona also underestimated inter, which led to their failure and Inter's Victory. But whatever the case was, it was indeed an unexpected turn of events.
I was one of such speculators who got disappointed at the end. There are teams that gets so mastered to a particular team such that whenever they meet, just expect some sort of fun because both team does put out their best anytime they are meeting and so it usually will look like they will do so well and that was the case with Barcelona and Inter Milan that inspired my speculations for them to get to the finals with those performances of theirs seeing that they also had a good squad depth as at the time.