Does the hand have pedagogical value? Any organic material would, but, you might has well replace it with a carrot (or other fruit/vegetable). Carrots are very conductive, as I learned once when feeding sheep next to an electrified fence. ;-)
We agree that the hand is somewhat problematic, but still find value in the learning goal related to measuring resistivity of biological materials. We suggest removing the hand for now, with an upcoming discussion about how this could be modified
by updating the artwork or by choosing another object.
In https://github.com/phetsims/circuit-construction-kit-common/issues/907 we decided to remove the hand circuit element. We have not yet decided whether we want to add some form of biological element to demonstrate its conductivity. Some relevant comments from the issue:
This is not part of the upcoming milestones.