iPhone 13 pro max dropping calls all the time seems to be problem with phone antenna

iPhone 13 Pro Max Signal Disconnections, Drop Calls, and Instability Across Three Replacements

The iPhone 13 Pro Max has a history by now of signal problems resulting in call disconnections or total signal loss. I've had three replacements tested at a local Apple store with the same result. The "RF signal receiver" fails the benchmark test. The problem has been around for a while with no software fix issued. Are we to expect a recall or do owners of iPhone 13s have to downgrade to iPhone 12s in order to have stable cellular service?

I've reset absolutely everything that could be reset on the iPhone 13 Pro Maxes I've had and still have the same problem with disconnections and power signal strength or instability. I've turned off 5G Automatic and went to 4 LTE to avoid some of the fluctuations. I've engaged Wifi calling and data roaming, as those were suggested by others with the same issue. I've removed the impact-resistant case to no effect. I've turned the phone on to "low data" mode to eliminate that as a contributing factor. Yet, the problem remains thus far, and given all the compromising adjustments used to gain greater signal strength, I'm thinking the iPhone 13 Pro Max is not a reliable and fully functional model. What is Apple doing to remedy this situation? Is there hope for a fix, or are we to just receive the same list of suggested user actions that result, at best, in temporary signal strength improvements?