How to prioritize Wi-Fi calling over cellular on iPhone in rural areas?

My iPhones have always struggled with wifi call dropping. This has only become worse as I moved to a more rural area where cellular has far more deadzones. While wifi calling is a carrier specific feature, HOW THE PHONE HANDLES IT is not. On my iPhone, as soon as I get even one bar of cellular signal, the iPhone tries to swap over, and half the time it drops the call. My android phones all handle wifi calling and transitions infinitely better (same carrier, same locations, same wifi and cellular). Outside of turning cellular on and off every time I want to ensure I don't drop half my calls, is there anything else to help prioritize wifi calling over cellular ON the iPhone, itself?

[Re-Titled by Moderator]