Monopoly, no. But Google certainly dominates education in the US:
"Today, more than half the nation’s primary- and secondary-school students — more than 30 million children — use Google education apps like Gmail and Docs, the company said. And Chromebooks, Google-powered laptops that initially struggled to find a purpose, are now a powerhouse in America’s schools. Today they account for more than half the mobile devices shipped to schools."
Again, I don’t agree they “dominate education”. That’s like saying that Bic dominates education because a huge percentage of kids write with a Bic pen or pencil every day.
Teachers who accept work with pen and paper will be able to accept work if non-Bic pens are used. Bic pens aren't used to drive classroom learning, collaboration, and assignment completion like Google Classroom, Gmail, or Docs. Bic pens also don't stop to correct you when you misspell a word or suggest that you use a different word when you've used one that it deems to be offensive to a hypothetical audience.
I'm not sure how someone can have a notable majority in anything and not be said to be dominating that thing.
The classic "think of the children" argument. Who could possibly argue against the children?
> By highlighting these words in their monopolistic product (Google Docs)
Google Docs isn't a monopoly, and you're betraying your bias in your criticism by pushing that narrative.