When I have lots of tabs open in Firefox, there are occasional pauses where everything, including the browser's chrome, freezes. I've never noticed these pauses in Chrome.
And yes, I do open hundreds of tabs. (As a side note, Chrome's far smaller minimum tab size is a major bonus for my usage, simply because I can see more tabs without scrolling the tab bar).
No doubt some portion of people upvoting this article are invested in a Firefox v. Chrome narrative, but that really wasn't the point of the original article.