There's nothing obviously wrong with assuming that "biology can do it with organic materials, so we should be able to do it with electronics" - while it's theoretically possible that we'll eventually identify some fundamental obstacle preventing that, as far as we currently know, computation is universal and the only thing that depends on the substrate is efficiency.

Since we have a much, much better industrial process for manufacturing electronic components, why attempt to make a biological AI if there's no current reason to believe that it being biological is somehow necessary or even beneficial?