Maybe a public service dating app makes sense. The alignment of incentives are all wrong for private dating apps. They obviously lose when you find someone and pair up so they're incentivised not to find a match.
Unlike other incentive systems, I feel like this one would be harder to abuse since there’s a fair amount of friction to getting married.
It's interesting how "honor system" can work for certain in-person businesses, but I don't think it could ever work for a dating app.
The amount pledged and the charity could be public for extra virtue signaling.
That's also survivorship bias. My friend met his GF at a sports-group. I've been going to that sports group for a year and didn't meet a GF. I met my ex-GF in a coffee shop. My friend has been going to that coffeeshop for a while and didn't meet a GF.
There's too much randomness in dating and variance between people, to draw conclusion that just because an app or social place/group worked for one person it will bring results to another.
There's no sure thing in dating apps, otherwise everyone would be on that one app and stop going out altogether if it were that easy to find a partner.