The problem
Drupal lacks a generalized facility to generate feeds.
Discussion
As it stands Drupal only creates RSS feeds. This is not a problem in of itself but it does set the tone for contributed modules. For example pathauto.module automagically creates url aliases as well as feed aliases but it only understand that it is aliasing the RSS feed. While it is possible to generate other feeds through the addition of modules such as atom.module there is no interaction between modules.
Solutions
Drupal needs a core module that handles generating feeds. This module needs to be able to let other modules know which types of feeds it generates in order to allow modules like pathauto.module to generate aliases for all available feeds.
My preference is to have a feed.module that houses sub-modules such as atom, rss, and others. This would allow for structures such as /feed/rss and /feed/atom as well a future feed types.
There are other benefits to a more modular feed facility, one of the other benefits is that it would allow for custom feed types to be installed and created easily. One other benefit would be to make it easier to upgrade a feed type outside of the Drupal cycle.