Creating a new social media like Facebook or twitter is not a problem but how do we have millions of users like those social media? This a task that will hard to accomplish obviously its a good idea or way of bypassing sanctions against cryptocurrencies by those media, we need to advertise, promote and publicize cryptocurrencies aggressively.
I agre with you because that is the way to promote bitcoin in social media that's why facebook and twitter was created so i think facebook will not replace by the bitcoin maybe there's a reason why creating social media,social media is better to promote bitcoin to have many investor's.