> why has no one made an app with the reverse incentive structure?

You've identified the problem but failed to adequately describe a solution.

The matchmakers need to make money, even to just pay for the costs of running the service.

A monthly subscription to use the service creates the perverse incentive to give bad matches. A one-time fee makes unsuccessful users feel cheated out of their money. A "pay us once you get married" option is ripe for abuse.

Even if the service is free and paid for by selling ads, you'd run into the same problem of the subscription model: They'd be incentivized to keep you perpetually single so you see more ads.