The OP brought in domains as an example but domains are not applicable.

Everybody on HN should know how a domain works. I think most people on HN understand what a hash is and how a magnet link works. The fact that you can't easily replace the resource under a magnet link is a feature not a bug. If you think for a bit about the consequences of what would happen if you could easily replace the resources associated with a magnet link rather than just having the 'convenience of being able to update a torrent' and you'll see that this is not a simple thing at all.

Torrents are simply a different thing than 'the web' and to try to equate the one to the other is about as silly as trying to say that you can't use a screwdriver to put nails in the wall. They're different things. Analogies are supposed to be useful, not a demonstration of your complete lack of understanding of the underlying material.

I distribute some software that I wrote using a torrent with a magnet link, so I'm well aware of the limitations there, but these limitations are exactly why I picked using a torrent in the first place.