Is it too early to start a startup in Quantum Encryption?

I have been working on the idea of prototyping a design for quantum encryption based on quantum entanglement and EPR paradox, some of the feedback I got was it is too early to start there. There would be no buyers. But in my vision I see the future where a full proof of encryption is not a luxury and a clear necessity with the amount of data being generated. Banks, Defense, any other firm with huge amounts of data needs a full proof encryption. The current encryption is inhibited by computing power than natural laws and quantum encryption is strong because of the quantum laws. I understand there are less people to fund such a startup and it is a long curve. however, I am thinking from the idea perspective does it make sense to start with a prototype design.