[...] basically the entire enterprise world.
Most corporate documents are transient: they are critical for a very short time, until a high-level decision is made, and then they're basically landfill. Contracts, sure, you might want to go back and look at them, but pretty much everything else is ephemeral. They use change tracking and comments, but hardly ever stylesheets.
Documentation, particularly professionally-written documentation, on the other hand, needs named styles, and this is where OO, LO, and GD fall flat on their faces. Word lets you set a style margin, where each paragraph-level object's style name can be seen at a glance. In other systems you have to hover or click or something on each object in turn. Editing or writing in this mode is a snap compared to OO, LO, and GD. Named styles are the only way that you can reliably get a reusable XML document out of a wordprocessor (ie not OOXML), and without proper facilities in the interface to manage styles, a wordprocessor is a dead duck.