I don’t think so. I think GP used the term monopoly when oligopoly would have been more appropriate. I use the term oligopoly but it’s quite common to say monopoly because it’s a very similar thing. Also Duck Duck Go is not comparable to Google Search or Bing.
I think the GP misspoke. It's more accurate to say that people are forced to use Google products. Even if you use DDG and Fastmail there's no escaping reCaptcha, AMP, and Google Analytics - unless you want to limit yourself to only a few websites.