It depends. If it is indeed a bug, reporting it is a favour to IPS so they can fix their problem and end up with a better product. Being required to jump through hoops in order to help them doesn’t feel right.
If it is likely an issue specific to a single installation and a custom server setup or third-party items, then that is a different story altogether. In this case, investigating it by IPS would be a favour to the site owner.
Looking at the code, it seems very likely that this actually a bug. The template just calls <a href="{$item->url( "getPrefComment" )}" … and that rarely includes Commerce products. So, this might have simply been overlooked.