It's one thing to remove the hardware/sensor and do it virtually via software to save cost. It might not be that good, but the capability is still there. This is what happens to proximity sensors on many Android phones, including the S20FE. The OEMs remove the proximity sensor hardware, and do it virtually via software using other sensors (eg. accelerometer, gyro, and the touchscreen itself to detect the position of the phone). Cost-saving, understandable, although annoying.Only thing I can think of is that a lot of noice cancelling is done via software these days (think: Discord) - I would imagine if a feature like this was removed, we'd be having a lot more people complaining about call quality.
What Apple is doing is literally removing a basic feature while the hardware (the multi-mic system) is still there.