There has been attempts at doing torrent-based package distribution, see the notes of debian testing it here:
https://wiki.debian.org/DebTorrent. There are basically 2 problems:
Packages are a lot of small files, and not everyone is interested in them all. Torrents are good for large content that everyone wants. The two are in opposition and there needs to be a balance: do you need to make One Unique Torrent with everything, but then peers have to individually ask each and every other peer if they have the content they're looking for, making it unscalable ? Or do you make one torrent per package, meaning peers have to track thousands of torrents ? (That's the direction IPFS took, which is why it's extremely inefficient and resource-heavy). DebTorrent has made the choice to go in the middle.
The real problem, to me, is that content-addressed content is the anti-privacy protocol: since you ask everyone "do you have this content", you're basically telling everyone what you want. In the case of installing packages, this means telling everyone what the version of your packages is, and is potentially a security issue.
But the real "problem" is that it fails at being much more better than the existing solution. Bandwidth is cheap, storage is cheap, so hosting everything on a few independent but centralized servers is good enough.