Well, the difference would be that I actually built radios, and at least some of them worked. It's really that simple, even without SDR. You already have a microcontroller that reads rotary encoder attached to the tuning knob and changes voltage that goes to the VCO (or divisor in PLL). All you need is to control it from CSPRNG.

You will need to spend some effort on getting synchronization right, but it's a lot less complicated than, say, building a CRUD app.