They probably sound slightly differently, and have more historical value to them. I just digitized my grandfathers cassette collection, because it was his, and are a different experience (because of how cassettes sound).

It is definitely possible, as RSS readers like ReadYou can do it. Maybe try FreshRSS in conjuction with an RSS reader?

I use ReadYou. Has more features and easier to understand than Feeder (at least for me).

Requires no permissions (except enabling notifications), can use local (on device) accounts. Only requires RSS links, no other data.

Supports notifications, have not tried it. Also likely requires background refresh, which I don’t use, so don’t know about that.