Plenty of blockchains—Filecoin included—use some amalgamation of IPFS, but the reverse isn’t true.

But one of them is directly tied to it.

I don’t use Brave, but from a cursory glance I think probably yes, it “uses/depends on” a blockchain for some functionality.

It's just a web page, the actual browser functionality doesn't depend on it. But maybe it wasn't the best example.