https://pagefair.com/downloads/2017/01/PageFair-2017-Adblock...
It basically is beyond imagination unless you think they have a new income plan that just needs one more quarter. Google's long-term value is in the conversion rates of long-term advertisers: drop conversions in half with fake traffic and next month they are going to offer you less than half the bid or nothing if they have high site costs per visitor. I.e. licensed booking listings.
Probably partners that share immediate revenue with Google but are less invested/secure in their portion of the long term value of that stream are behind it.
Being cynical makes sense, but then it is actually more likely that Google has been generating fake traffic on fb than fake traffic for itself and vice versa. FB spent years being irrelevant to much of the market while getting a lot of money from less savvy advertisers for bot networks. I don't think the short-term revenue was worth it to them and I would be surprised if their exec bonuses weren't mostly hurt by missing targets and losing big advertisers.