How is it convenient? A pro workflow is not holding your arm with the finger up in the air trying to avoid accidental taps, when you can get a small 25 key akai midi controller for a 100 usd. And it's easy to carry around and comes with velocity-sensitive keys and pressure-sensitive pads.

Yeah that's a much better use case. Now you mention it I could see it being useful for soft synths, mixing, arranging, effects, etc.

I don't think I'd every want to "play" on it except as a last resort but it could definitely be handy for other virtual interfaces.

Imagine a knob per function synth or a modular setup being able to go straight the control in question would be useful.

we have computer keyboard playing mode in nearly every DAW under the sun. It's useless