I think it's just a coincidence in this regard but indeed in the last 1 decade coincidences like this keep happening although this season I'm not sure it can happen again.
At the moment Inter have Marcelo Brozovic in their squad who incidentally is a Croatian player but in this case I dare not expect much for them because even in this case Manchester City do not have a Croatian player in their squad but with probabilities they are still Manchester City favorites in this regard .
I don't believe on this theory,all those winners with a Croatian player were all co-incidence. Are you trying to say that the champion league victory will on be won by a club with a Croatian,meaning the league is made for Croatians. You have concluded from your own point of view,let's see if it will work out the way you said. Moreover, Manchester city is likely to be favored in the finals because they have the quality of players to win the game.
Inter is going to play a defensive football as usual but I don't think that will work for them because Manchester city has good strikers that will destroy any defense in the world to net the post. They are good in striking from outside the box and inside the box. Inter loves counter attack,which might be their only strategy which they will come up with. The finals also depends on luck,the must lucky team on that day will win the trophy.
As I said earlier this is a coincidence and indeed too often in that case but it's not a mistake of coincidence but indeed we see other conditions that in this case Croatian players are really good because they are at a club that always wins there.
But then again the possibility of that now being broken by Manchester City and even if it's not certain but my hope is that with the probabilities now it's very good for them.