The frustrating issue is that they don't state in what situation. I'm certain that most people will just do fine with only 100 kanji characters for daily life, or no kanji at all if they're just a tourist. But if you're applying for a full-time Japanese speaking job in a Japanese company, knowing only 777 characters is a joke (which is about the 5th-grader level). Just like a programming language, the level of fluency required depends on a task.

p.s. just confirmed that the list is not enough for filing a tax in Japan. They don't have words like 所得 (income), 控除 (deduction) or 医療費 (medical expense).