I think they're just rumors as of now. Correct me if I'm wrong.
First Facebook, now Google. I don't blame Google though. Those ICO and cryptocurrency are just either trash, scams, or shit ICOs. Remember those Binance, MyEtherWallet, etc phishing ads? Yep. People keep on clicking on those phishing link ads so Google has to do something about it, and here it is.
There has been news circulating about this all over the internet but we should only trust an official information from Google regarding this. As you mentioned, this is certainly possible keeping in mind so many suspicious ICOs being launched everyday. Because of few people , whole crypto community will suffer and even bitcoin prices will decline rapidly if Google really implements this. In the past Google has banned affiliate links like those of ClickBank and it affected the affiliate marketers badly.