You're completely right, people are lazy, but online dating is also way more work than it has to be. Women receive so many messages that it becomes overwhelming and too much work and men try sending earnest messages for a little while and then concede that it's basically a numbers game. These two phenomena are self-reinforcing. The more messages women receive, the less likely they are to respond. The more messages a…
Your solution is Hard Security when Soft Security is way enough (refer to meatball wiki for more on these notions).
Not only that but this problem has already been solved a few times, a simple and effective but not perfect solution: a man cannot message a woman until explicitly allowed by the woman. a man can notify a woman her profile caught his interest with a poke-like of which he gets a limited amount per day. There goes the message overload for women issue.
Now remove the heterosexism component and make it so no one can message anyone until explicitly allowed by the recipient and not only you got the message overload issue under control but you get an incentive for people to put some care into writing their profile and reading other's.
There's probably a better way, but this one is IMHO at least an order of magnitude better than your proposition.
The solution is in challenging how we suppose this should work and not in trying to fix those broken assumption by placing additional layers on top of something defective by design.