Its not them who is banning crypto ads but the FBI and other government agencies forcing them to do so. Why would these websites ban something that is the future and the younger generations are interested in. Also this is a positive news for the crypto world as this will prevent the new users from getting hacked or buying into scam ICOs.
your opinion is very reasonable, but I also agree with the OP because even though bitcoin advertising is banned on facebook, twitter, Google. there will definitely be other ways to promote Bitcoin.
broken one grows a thousand
(everything that has been lost, definitely there's a replacement)