From the article: Alonso describes the app as “a demo of Samplr for the MacBook Touch Bar.”

Samplr is Alonso's full featured iPad app.

From the website: *This free app is distributed as is. No support is provided and no future updates are planned.

That said, I'm sure a talented and adventurous person could off pull using this. You define your limits =)

Professionals actually do use the Touch Bar. Oak Felder seen here using it back in 2018 to produce on the go:

https://youtu.be/FUHcYX1-9Y8?t=178

I'm not a proffesional, but I use Garabe band to brainstorm ideas for songs, and often I use the software piano keyboard and it's annoying because you can hit other keys that are not assigned to notes but to shortcuts, and you have to show/hide the piano window that ocuppies space, so I can see having a piano in the touch bar (and other plugins for that matter) being super useful.