As far as I’m aware it’s been confirmed that there’s no physical switch in the center that can act as a horn. Now it is possible that their plan was to detect a center press in some typical Muskian overcomplicated method of using the interior camera or something and they never actually got the software to work.Over a year after the promised update, no go? Does that mean the hardware was never there as promised or they're still woking on a software update? The tweet said all cars after Nov 2021 I think have the hardware.
There is some evidence that they were planning for a center horn at some point Elon Musk confirms yoke steering wheel airbag horn will be turned on through OTA software update
Though for all I know that picture was staged
Perhaps the model 3 highland steering wheel and airbag would work in the S/X and that does have a center horn. But the diameter is probably small enough to obstruct the instrument panel. And I don’t know if there’s be any potential issues as far as the airbag goes.