Shucks, we could cob-ble together an amaizing proof-of-concept to bag a bunch of investors, although those folks can be salty, so they might need buttering up.

Nah, the real money is being a MaaS provider. (Marketplace as a Service). Why try to strike gold when you can just get rich selling the gold-rushers some picks and shovels? It shouldn't be much more than an API and some customizable matching algorithms (e.g. proximity or pricepoint or keywords and maybe a scheduler or two).

I'm only half-joking in that I wouldn't be surprised to find out this is a thing already.

That'll hurt the movie industry a lot more than file sharing. Expect some lobbying on both sides.