@greatninja3: in a sense, it is, but I get your point. If you read a bit in this chapter, when he finally chose to confess to Chise, he felt relieved, like he already had feelings for her beforehand. But instead he run the app with other girls looking for better scores, making him lose time and maybe the thing that made him be too late. (In fact I'm convinced because it seems that she started dating when he was reviewing the other girls) It's not lacking confidence in himself in the general sense, but in the decision he's making.
And as for this app... I personally hope that something like this never exists. I see it that it has the exact same flaw dating apps/sites has:
It depends on user-submitted data from various sources. As the asshole doctor says often:
people lie. It doesn't even has to be malicious lies, just havin a self-image a bit off of how you really are, for better or for worse is enough. That's why, even the dating site/app admins will tell you, that is better to actually contact and know the person in conversation, for it's usually harder to lie in person than in profile. That render those sites as icebreakers and first contact, but that's it.