“I cannot believe that there are people who advocate radio silence.”
In VMC for a radio to be considered in collision avoidance you need to know that everybody has a radio, which is not the case, that they are all talking to the same station, which is not the case, and that any RIS which might be available can see all the threats, which is not he case. Many aircraft operating on hand held radios have very limited range and battery life so only use radio for t/o and landing.
Rod1