Iroh got started with IPFS-style content-addressed blob transfers as the primary way to use it, still has that functionality but its now a bit of a second tier citizen. See https://docs.iroh.computer/protocols/blobs

Besides just p2p streams seem to be much more useful, those are plug-and-play into most software, e.g. I wrote https://github.com/magik6k/git-remote-iroh that just plugs the git remote proto into iroh and lets you move repo commits between computers by just copying a string from one place to another on push. Doing that with blobs - not gonna happen, not that easily.