Yes and no. As is known, social media is almost owned by everyone. So by advertising bitcoin in social media, somebody will know bitcoin and they will look for it and may even ask the person who advertises the bitcoin. Finally, bitcoin becomes popular among social media users and even spreads by word of mouth. But some also use social media as an intermediary to overthrow bitcoin by spreading false news about bitcoin and innocent people easily affected by the news.
Yes, I think so too. In fact, social media is an important medium of communication. Through the spread of social media, more people can know bitcoin and thus its market value.