Why not have rollbacks of non WP.org plugins?

[mkormendy]

Just curious why you couldn't simply

1. store a zip file for every current plugin moving forward
2. every time a plugin is upgraded, zip up the current version before upgrade hook is fired
3. allow any plugin with existing versioned zip files to be rolled back to

I also realize:

• that your plugin ties into the wp.org version history, but there could be a check to see if there are local versions already on the system first?

• that there are some issues with custom db table changes in plugins, but how do you handle those with wp.org plugins that have custom db table changes?