You've never said "Hey, I know you're wrong, let's bet on it!" on the internet but never been able to go much further? I know I have! Plus I've definitely wanted to play 1v1 games for a bit of money (video games that is). And many others have, as people solving this issue are raising millions and have thousands of users already :)

You may not personally find it useful but it's much harder to solve on the "Web2 stack" than the "Web3 stack" if such descriptions exist.