This doesn't solve anything. The core problem is that women get tons of spam messages and men get very few responses. This means the matching algorithm is broken. This site is just a tweak on hot or not.
The first is that dating sites typically don't care about people actually finding a good partner, because there's a negative economic incentive for it. If you find your perfect man/woman, you won't come back to the site and keep paying.
The reason why women typically get loads of spam is because many sites are expressly designed to encourage this. A common pattern is where it is not made clear whether or not a profile is active. Since only a small percentage of profiles on the site are active, it's hopeless for a guy to try to send detailed, personalized messages -- odds are, they'll all fall on deaf ears, inactive accounts.
This is intentional -- because it lets the site appear as if they have far more profiles than they actually do. Once they've suckered someone into paying to send messages, they find that they get almost no responses, and end up finding themselves forced to send hundreds just to reach a few live people.
Which of course leaves the recipients flooded by spam... so they leave. Adding to the glut of inactive accounts.
Combined with the general sleaziness of the industry and the type of people who use general-audience dating sites (read: the type who tolerate all these problems), it's no wonder the entire industry is a disaster.
There are definitely niches available for matchmaking sites not built around the typical model, that try to pair up people for long-term relationships based on what actually matters instead of providing sex-starved 20-somethings with people of the opposite sex to ogle. But it's hard to market such a thing, even in a specific niche, because the entire industry tarred themselves with their own brush, leaving a huge number of possible customers permanently turned off from the idea of ever using such a service.
Dating sites that think like this are in no actual danger of having their users fall in love. It's hard enough even for well intentioned sites to set up enjoyable dates, let alone ones that lead to marriage.
If anyone actually had a dating service that worked so well they were losing users due to excessive happy relationships, that would just mean they weren't charging enough to get in: Imagine what people would pay for a service where 30% of all users end up with the love of their life within a year. Hell, imagine the marketing value of having large numbers of satisfied couples going around telling people they met on a particular site.
This matching algorithm has carried us, humans, through millions years. Various opinions and statements can be made about this algorithm, yet it is definitely not "broken" :)
To be honest, its a lot like recruiting - the people sending their resumes to every company on monster rarely get hired for the best jobs. Those jobs instead go to the "good looking" people on LinkedIn, who are approached directly.
No reason this app can't work the same way.
And don't forget, Hot Or Not was an insanely successful dating site.