On paper, PSG might look better than Borussia Dortmund because PSG does have a better composition of players but that doesn't mean that they will be able to win easily against Dortmund because teams from the Bundesliga will always have their own motivation when competing in the Champions League and usually they will be very tough opponents. PSG could indeed get rid of Barcelona, but I think they got it after Barcelona made a very stupid mistake. If Barcelona had played with 11 men in that second leg, I don't think PSG would have been able to win against them.
Dortmund don't have many star players like PSG but if with those players, they managed to beat Atletico Madrid in quarter finals, they have abundant confidence that they will be able to beat PSG. It's a big warning for PSG before two semi final matches because at this stage, mentality and ambition will mean a lot for a competitor.
Dortmund are not worse than PSG too much and with better team mate cooperation of their players, they have strength that PSG don't have. Dortmund don't rely too much on any single player and their strength is very decentralized among their players. With PSG, if Mbappe is controlled, they will have big troubles with tactic operation and can be beaten.