One thing that bugs me is that
computer networks (and especially the internet)
are not filesystems, if you look at modern
unices.

What if I want to download all images from an
instagram account? It is unfortunately not
as simple as
and then just use to copy the images.
Instead, I can do two things: spend one and a half hours
reading the wget manpage to find out how to this, or write
a small script with an ad-hoc parser using curl.
But if I want to reuse this another time, I will have
to write another parser.

My main complaint here is that we could treat data
on servers as filesystems that could easily be mounted into
the local file system (this is, obviously, what plan 9 does).

One could argue that there are FUSE systems for that, but
this argument does not count. Why?
Because FUSE systems are specialised, and can mostly be used only
for one website. For another website, somebody will have
to write another FUSE. I can't accept this as a viable solution.

Imagine what e-mail would look like in a world where you
can mount servers as file-systems. You log into that server,
ls your inbox, mount another server, go to your friends directory,
edit a mail for him, save it on the other server, unmount the two
servers again and then proceed. I don't know how you feel about this,
but I wish so much that this could come true.