This is a helluva way to open an article about ad scams:

In 2020, AirBnB cut $542 million of performance advertising spend and saw no measurable falloff in attributable sales. They continued this ad-slashing practice in 2021, with similarly eye-popping numbers. Could it be that all those ads did nothing?

Source: What if Performance Advertising is Just an Analytics Scam? – SparkToro

Really interesting and thoughtful take on the fast changing digital ad landscape.