“That’s less than ideal for one key reason — there will be no hardware visualization to show whether the phone is muted or not.”.
Visualization, ummm Seriously? There’s very modest visuals regarding the current mute switch being on or off. Otoh that mechanical switch on a small surface can be very tactile. It’s easy to feel the switch is up or down. If Apple does go to a solid state switch, tactile is definitely gone unless there are haptics (seems unlikely for the mute switch imho). From a visualization pov, very very minor red illumination would be a far better visualizer. But it is unneeded. the best visualizer when in mute mode is make dynamic island be lightly outlined in red. You can’t miss that. Place it on the Lock Screen too.
I know some love the mechanical switch but a solid state switch is superior in a number of ways. And it should be firmware connected (will work if iOS is stuck).