That we disagree is no problem. We are each entitled to our own opinions. And the discussion is just that, a discussion about opinions and about how one comes to those have those opinions.
But, if a person claiming to be fluent in a language goes to the country where that language is spoken and can neither understand not be understood by the natives, then that person was either mistaken in his belief of his fluency or lying about it. If a person claiming to be a plumber does not know how to tape a pipe joint, then that person was either mistaken about his belief of being a plumber or lying about it.
So, what shall we say about a person claiming to be a trained and titled philosopher that does not seem to know the simplest things about valid logical, philosophical discussion and presents arguments not worthy of a bright high school sophomore?
Feel free to take pot shots at me, but, please, do not take pot shots at what I am.
You've made claims. When you fail to live up to those claims and someone points that out, they are not attacking who you are, only who you say you are.