The Banner had something basically seeing the same thing, and asking the same question.
One of the former plans had a walking bridge. Ultimately seems like that would make more sense.
Problem with a walking bridge is you need something with a high enough clearance that large boats and/or visiting tall ships can get under which means lots of steps to climb. Or a drawbridge type of thing. I haven't lived there in over 16 years so maybe things have changed, but gondola or bridge, trying to build a permanent structure so people can get from Pier Six to the Scupper quicker than a water taxi seems like a solution in search of a problem.