Last I checked, Google does not have that feature. There's an open-source project to extract them for you, though: https://github.com/lucasrangit/google-podcasts-export-opml

I started hunting for a new podcast platform when Stitcher announced they were shutting down earlier this year, and I settled on Podurama. It's the only one I can use on any platform, including desktop Linux (via the web version, which is actually quite good). I can subscribe to private feeds (e.g. from Patreon subscriptions), it syncs play history in my account, and it allows me to mark episodes played in bulk so manually porting over my listening history was not as big an ordeal as in other apps/platforms.

I'm using it for free, though they do offer a paid version with some very minimal additional features.

Edit: I would much prefer an open-source solution, but I have yet to find one that works across platforms and syncs between all devices. Open to suggestions if I missed anything good. At minimum I need an Android client and web client (or if they actually make apps for Mac/Windows/Linux/Android and somehow don't have a web client, that's fine too, but that seems unlikely).

You might be able to grab them from takeout.google.com