Scripts using #!/bin/sh instead of #!/usr/bin/env (ba)sh won't use your shiny new shell. Including scripts deep inside the build system of misc. software that you won't modify.
The only way is to set their strange /etc/private symlink (cf sh(1)) to change what /bin/sh execs, and to do it again after each update which resets it.
The only way is to set their strange /etc/private symlink (cf sh(1)) to change what /bin/sh execs, and to do it again after each update which resets it.