The famous last words.

Of course they are overwhelmed by the taks of keeping AdWords clean, just like Apple is overwhelmed by the task of timely approving apps for App Store, despite having more money than god and the number of AdWord ads submitted to Google is several orders of magnitude greater than number of Apps submitted to Apple.

Processes that involve humans are inherently non-scalable and determining whether an ad crosses the line of acceptable usage is a human task.

And humans have different opinions so there will never be "evenly applying guidelines", not for google ads, not for App Store apps. The only time 3 people have exactly the same opinion is when 2 of them are dead.