Facebook have it new policy pertaining to initial coins offerings 'ICOs' . The policy specifically prohibits ads that promote ICO on it platform.
The banned is due to the fact there are so many companies who are advertising ICOs that are not currently operating in good standards and faith.
In the meantime, Facebook is encouraging people to report content that violates this new policy.
What effect do you think this will have on ICOs and future of cryptocurrencies?

The crypto community is strong enough these days and can resist it. It doesn't matter Google, Facebook or anyone else has decided to ban ads related to crypto. The other projects used this opportunity to promote their products. Pay attention to such products as desearch.com or matchico.com They are related to crypto. Besides, there exists a lot more.
Whatever it is really does not matter as the market is still standing strong and there are so many other measures that can be used anyway and not like they are completely limited to social media adverts. The way some people are saying it though, it is not like some ICO adverts are not still running and all you have to do is to be able to show you are for real and not just some fake project looking out to scam the users.
This was done to clean up the space anyway, so I do not see it as something bad or an attack on the crypto world except for some who just love reading negative meanings to everything.