I'm not sure what the foregoing was supposed to mean, but your closure is the Fallacy of Truism: thinking you have a closing argument by reciting a common fact that has no bearing on the discussion.

Of course credentials are words. Words are what we use for communication. You cannot present evidence or logic without words to describe either and their relationship to a case or argument. "I sentence you to death!" says the Judge. Just words, words, words, right?

More to the point, having credentials gives some "credit" to what you might say for anyone who does not know you. If you want to dismiss the person with credentials because they offer "just words, words, words," then you are obliged to throw out everyone else as well, because that is all they are offering---without the benefit of any accreditation. You are not in a position to judge either evidence or logic if your own understanding is ignorant. So now comes the question: Who to credit? One mark is whether the person has the education, training, and/or experience to make statements pertaining to a given subject. Another mark is the person's willingness to take questions and explain with reference to examples. A third mark is how well the person's account squares with reasonable third-party references.

The problem with the internet is that radical egalitarianism obliterates any meritocracy. A complete boob can make pronouncements that are lunacy, but can assert he Knows It All. The trained scientist can argue and criticize the boob, but "they's just words, words, words." So, either you pay attention to credentials to give you some measure of the words a person says, or you have to put corks in your ears because "words, words, words" are worthless (as you imply).