It's come to the point where the content on my Home tab and Following tab feels like it's from two completely different worlds. What's going on here on this site?

That's a great observation! The 'Home' feed is algorithmic and designed for discovery, showing you popular casts or content it thinks you'll like from across the network. Your 'Following' feed is a chronological list of casts only from the people you follow. It's like having two modes: one for discovery and one for ...

Sensible answer but in practice it fails completely