Just to play devil's advocate here.
Banning ads doesn't really matter for prices. When did you ever see an ad for a big coin on facebook anyway (other than maybe dash). The real coins with real value don't need bullshit ads to promote positive price action. They do it through regular work and updates.
A lot of the crypto ads that we saw were for bullshit coins (like BitConnect) that were essentially taking money from idiot consumers. Sure you could argue that it's anti-competitive, but it's pro-consumer. We have laws that look out for the little guy and I applaud Facebook for banning ads that are misleading and potentially harmful to consumers.
Just my two Satoshi's.
RE: Facebook's crypto ad ban is anti-competitive and misleading