Not mentioned in the article but WorkFlowy (YC ‘10) is still going strong. Minimalist web-based word processor with a flexible outline format. Can hold hundreds of thousands of items, without you getting overwhelmed.
I'm a Workflowy user but would never describe it as a general-purpose word processor, even with the "minimal" modifier. There are no formatting tools whatsoever. It's more of a minimalist mind-mapping tool.