Why is the Google Search Results page not responsive? [closed]

As every web developer/designer, I read many articles about why responsive web design is important. We are also often told, that you can learn a lot by observing the UI (and optionally the code itself) of large, successful companies.

Today I wanted to browse Google's result page on the left side of my screen and I noticed that the page is not responsive, even though it'd make sense and, even for a beginner, wouldn't be difficult to do so.

Why did Google decide to not take the responsive design approach for the result page?

I hope to see answers and I hope this question won't be closed.