> asking a web browser app to remove references to all the websites and social media posts
Except usually a web browser doesn't include a index of sites, You go to a another site (Google/Bing) for that. If a browser does include "recommended sites" the landing pages of those sites best keep to Google's and Apples rules. For an extreme example, If Firefox was promoting PornHub on the new tab page we could understand why Google or Apple would tell them to cut it out, but it doesn't stop you from visiting the site.
I'm not saying I agree with what Google have done here (IMO they should re-instate Podcast Addict), Just that I can see why Google could think "recommended podcasts" and podcast indexes come under the "included content" of an app.
EDIT: As others has said here, It's more like Google banning YouTube because it contains video's about covid 19 which don't come from "approved sources" (Though Google did demonetize people for talking about it and de-rank non "approved sources")