Actually not sure which team will win the UCL title this season. But I would probably choose Inter Milan because I have liked Serie A for a long time. So choosing a team that comes from there might be more to my liking. But that doesn't mean I don't like PSG because I also always like to see their style of play which is never boring with its fast attack strategy.
However, as we can see in the head to head picture, PSG is actually the favorite. In the last 5 meetings we can see PSG winning 3 times, drawing 1 time and losing 1 time.
If we have to choose based on the performance of which team is better. So it will be difficult for us to determine which team we should favourite. but if we choose based on which team we like more then yeah it will become easier. But because this is a matter of risk in betting. Then we have to judge which team will win in the end no matter it is a team we like or not. It's just that for the UCL final this time the two teams looked evenly matched. So yes, I also prefer to choose the team that I like more. And in this case my choice is the same as yours, namely Inter Milan. 
However, as we can see in the head to head picture, PSG is actually the favorite. In the last 5 meetings we can see PSG winning 3 times, drawing 1 time and losing 1 time.
And yes, regarding the h2h history of the two teams, it looks like PSG is superior. But we can see that in the last meeting it was Inter Milan who won. So we cannot use H2H as any reference for the final match.