Parser not parsing all fields on (some?) Podcasts?

For certain podcasts, such as: [https://rss.art19.com/id10t](https://rss.art19.com/id10t)

When calling ```FeedParser.parse``` or using a concrete parser, the resulting ```ParsedFeed``` has ```nil``` fields, such as ```feedDescription```.

I also tried with the Joe Rogan Podcast:
[joeroganexp.joerogan.libsynpro.com/rss](joeroganexp.joerogan.libsynpro.com/rss)