Google's CEO declared it's "AI first" and they developed TensorFlow. If they wanted to, they could have easily prevented those ads from entering their network.
But yes, if they wanted to, they can divert their more advanced ML teams to tackle specific issues like this first and get it done. I really doubt this is a high priority issue for them.
Google has machine learning technology that automatically reads street address numbers on houses, regardless of angle, color, size, focus, or typeface.
Using the same type of algorithm to answer "does this ad have anything that looks like a button in it?" is relatively simple by at least two orders of magnitude.
So rather than it being "easy" in some absolute sense, what's meant here is that it is easy compared to similar tasks that we already know Google does routinely and has largely automated.
- Is this a download page?
- Does this ad contain a button-like image with the word "Download" on it?
Presumably the people creating these ads are specifically targeting pages with the word "download" in to create this confusion, it doesn't seem like rocket science for Google to apply the exact same rules.
And changing the images to evade the algorithm would also directly affect how likely they are to trick people, so it's win/win?