Syncing doesn’t work

Does syncing between the podcasts app on different devices work for anyone, ever?

I use the app on my iPhone X, iPad Mini Retina, Apple TV 4K, and Windows 10 PC and no device talks to the other. They can pick up a new podcast subscription, but that's it. They don't know if I unsubscribe to a podcast, and that have absolutely no idea which episodes of any podcast I've listened to. I end up with huge unplayed lists on the devices I use less frequently, even though I'm fully up to date on my iPhone (the device I use the most).

Is it just me? I've tried installing and reinstalling, but it's just broken.

The app just seems defective in general. Downloading on 4G never works automatically (I have to manually trigger a download, despite it being turned on in the settings), and the app never displays a badge on its icon (I have that turned on too).

It's a pretty weak effort.