I push this concept at the start of every project and when doing a post mortem this is always they area that caused delays and contributes to going over budget. Too much is changed and added at the end because the content was never vetted. Getting this into the SOW and communicating if the content is late the project will get pushed back helps (after all this is business). However, without it clear upfront and without senior management support a UX designer would have a hard time selling this through.
For article examples I like to use articles about writing good articles for the web like — https://blog.quiet.ly/industry/how-to-write-for-skimmers-and-visualize-the-text/