Podcasts can be purely entertaining, but there's always room to sneak in important messages if you want. As an example of how to do this, let's look at Barbie.
Barbie had a "dream house" in 1962. That doesn't seem progressive today, but this was at a time when women couldn't get credit cards in their own name. And mortgages on a home often listed women as "and spouse."
Barbie showed young girls that owning their own homes was possible.
A stretch? Maybe. But early Barbies also showed young girls career options that women during that time didn't have the option for – she planted a seed.
Today, most girls wouldn't think twice about being able to be a doctor or other "traditionally male" careers.
Your podcast can also change culture like this. An "entertainment" podcast that subtly delivers progressive messages can bring about change just as easily, and maybe even more effectively, than an educational one.