For me as an audience member, the turnoff behind
laptop performance isn't the lack of showiness. It's
the gradual loss of faith that what you're hearing is
being created "live". Watching a laptop performer, you
don't really know to what degree he's creating the
music in real time. He might be just hitting "play" on
some audio file or automated process, or he might not
be. You don't know. I feel the same way about
instrument players who use prerecorded tracks and drum
machine programs as background for solos.