Of course mice are cheap - how many billions do they sell? And of course controllers send the same midi type info for the most part. But most of us aren't programmers. Playing a piano looks simple - you just hit the right keys. That knowledge won't put me in Carnegie Hall, tho.
If you want something simple (pick up and control) it needs to be preprogrammed, ie. DAW specific. Even the VS 700's 32 buttons were hard to figure out although they were all mapped fairly intelligently. Even with scribble strips (which they didn't have) it would be hard to slog through all 32 of 'em to find the one you are wanting - a lot harder than reaching for an EQ on an analog mixer where all the knobs follow a map and are individually labeled and none have dual functions (or more).
The only way to make a physical controller cheap is to have it universal, and once you have made it universal it won't correspond to a physical map. So you are left to try to limit the software (like Softube does w/ their controller) or the user has no idea without a lot of training which button/knob corresponds to the button/knob on which screen. The logical conclusion is to have the enough physical controls around a screen and have the screen correspond to the DAW.
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