No, it really isn't. The Guardian article is factually reporting on what the "whistleblower" told them, both via the video and in a separate interview. They did not fabricate any details, or make any claims they knew to be false. They made a cursory attempt to present the other side of the story. Sensationalized, yes. Slanted, yes. But not fake.

Also the Guardian isn’t owned by a Google competitor - it’s owned by the Scott Trust, an organisation set up specifically to maintain the paper’s editorial independence.

They have viewpoints which include a distrust of very powerful global corporations, and one you may or may not agree with - but it’s nowhere near ‘fake news’.

https://en.m.wikipedia.org/wiki/Scott_Trust_Limited