Here's what Google said:
https://support.google.com/adwordspolicy/answer/7648803My first comment is that there's never been any
BTC advertisement. Who would pay for it? The
BTC's foundation? This board's webmaster? As there's no corporation, nor an individual owning
BTC, there can't be any kind of advertising. The only ads I've ever seen were for lousy ICOs, shitcoins, trading and exchanges websites where you can make a deposit but not a withdrawal, trading consultants who screw you with the promise to show you how not to get screwed, and super safe crypto-wallets where your private keys are automatically sent to a smart angel in East Russia. Google wants to ban all that? I say thanks Google!
As you've said, this measure was taken to battle all the scam involved around cryptocurrency, not cryptocurrency itself. We've all seen shitcoins, ICOs and so on popping up every day, so-called Bitcoin generators being advertised and many other malicious examples, that's what they want to ban, in order to protect their users. It's not hard for someone inexperienced to fall in their trap.