It's like in that meme: it's not enough to say it, you need to declare it.

Or, in other words, what makes a standard a standard is that you declare that it is a standard. This declaration carries with it an obligation to respect the standard for ever and ever (like C89), regardless of whether in retrospect you realize you've made mistakes and want to fix them, or maybe wanting to add more stuff etc.

Having a standard is restrictive and uncomfortable for the designers, that's why many opt not to have a standard. Eg. Rust language doesn't have a standard (even though you may, of course, find documents detailing how it works), same for Python, Java and many other popular languages.

Maybe He means because it diesen have an accepted rfc