Apart from the line "does it help in some ways, sure" the overall message of their post is that the author is wrong and that you can be equally successful without being sociable, which is a general statement.
It's not really supported by the anecdata that OP is a skilled, unsociable, successful person. That only tells us that this person, in their particular line of work, with their particular set of skills, can be successful. It also doesn't consider whether a version of them that was more sociable would be more successful.
Yeah but the statement in question is (quote) "you can be EQUALLY successful as an introvert" - and we're talking about whether people should, generally, strive to be more extroverted at work. That there exists a successful introvert is not in question and isn't a good criticism of the article to me.
Is it really not clear from context? "If introverts made an effort to be more extroverted, would it make them more successful?" Success I don't know what OP meant, but pay, seniority, I don't know that it changes the answer much.
It's not really supported by the anecdata that OP is a skilled, unsociable, successful person. That only tells us that this person, in their particular line of work, with their particular set of skills, can be successful. It also doesn't consider whether a version of them that was more sociable would be more successful.