I disagree. It changed how I think about JavaScript a little. As such, it was useful for me.

Be mindful that you do not mistake what we think for how we think.

I think the point the article makes is good, I just don't like how the comparison was made. I don't think the article would be of less value if the author dropped the "JavaScript is C" peppered all around it.

It's a fair point. That's the trick with a blog post where you're basically "thinking out loud." This is just the way that the little switch flipped in my head as I was thinking through things that day: The experience felt very similar.

Is there a difference between "I don't like this" and "This is not useful"?

There is. But in this particular case I stand by my point, a cursory glance will show that JavaScript is nothing like C. Starting an article with such a premise and re-stating it repeatedly smells like clickbait to me. Also it devaluates the point made by the article which is actually good.