Yes anything can be done in any match but in the final match as the pressure is a bit more between the two teams so in the final the big teams often lose under pressure.
We all consider Manchester City as favourites, but the result of this match can change at any time if Inter Milan take extra tricks. I didn't say I won't bet I just said win lose I won't bet I'll bet on goals. That is, I want to bet on this that there will not be more goals in the ucl final match.
And as you said bet on the team with more chances to win but not considering the favorites in the UCL finals those who do well on match day will win in the end.
The big teams don't often lose under pressure in final games, otherwise they wouldn't be big teams. It is more likely that we will see a more careful Manchester City than we are used to. They won't be pressing as hard from minute one, but prefer to get some control over the game during the first 10 - 15 minutes and then go from there. They could gradually increase their pressure with and against the ball gradually as soon as they have an idea how the game is going to develop.
Neither team will feel the urge to score a goal early and Inter will also be fine with letting some time pass by before they decide to take the initiative and raise the pressure themselves. If at all they are going to do that or they rely on counter attacks the whole game, but even that could be a conclusion or decision they make after the first minutes went by. None of the teams wants to let go this opportunity and they will play more carefully accordingly.