Because it's a text interface, not a gestural interface.
If you really want a gestural interface you can add it to any language that supports for MIDI control, or some other hardware connection option. (UDP, etc.)
The gestural part is trivial, just as putting a knob on a synth is trivial. The hard part is getting the knob to do something,. Which is not trivial at all.
In fact it's impossible without using numbers somewhere in the make-it-work chain. They may be a few levels down, but they're always going to be there.
If you really want a gestural interface you can add it to any language that supports for MIDI control, or some other hardware connection option. (UDP, etc.)
The gestural part is trivial, just as putting a knob on a synth is trivial. The hard part is getting the knob to do something,. Which is not trivial at all.
In fact it's impossible without using numbers somewhere in the make-it-work chain. They may be a few levels down, but they're always going to be there.