Well articulated need gap. I have previous experience in building privacy focussed dating platform which gained decent traction but had to shutdown for reasons unrelated to the product itself.
Dating platforms get away with privacy abuse as they project user's intimate private data as the foundation for their matching algorithms, which is true but doesn't give a free chit to the platform owner to use the data for other purposes.
Decentralized platform by definition is against commercial interests as they are not scalable so it is always out of favour from data hoarding corporations. But as you've mentioned a decentralized platform is definitely one of the solutions to privacy proof dating platform.
Peer-to-Peer matching without a central service on smartphones are currently limited by the communication technologies, mainly due to the security implications. There has been attempt to create P2P protocols like AllJoyn which can avoid friction like pairing requests (Bluetooth) but hasn't see huge commercial interests due to fragmentation in smartphone ecosystem.
A city based decentralized dating platform which uses proven decentralized protocols like Matrix protocol could be the best bet for this solution. Let's hear from others.