IPFS is a decentralized network protocol, a content-based addressing system. Filecoin is decentralized file storage, incentivized by cryptoeconomics. On their own, neither IPFS nor Filecoin have the same goals as Vapor. It seems as though Vapor's intended purpose is to use off-chain Bitcoin transactions to transmit HTTP requests to normal APIs. The primary benefits being (optional) payments and identity.
The document says it’s network protocol agnostic because it only focuses on decentralizing the data layer, so it might be possible to use vapor on top of IPFS in addition to HTTP
