I don't accept the downside that you mentioned about diversification in social media leadership. Yes, the task may seem daunting but necessity is more important than the difficulty associated with it. Creating a new culture would come naturally to those who belong to those cultures. Those who do not make change are doomed to embrace the status quo.
On another note, reforming social media will not be an easy task and I love that you described the benefits and drawbacks of each proposal for change. Yet, we must forge forward despite the difficulties and create the changes necessary to provide safe, inclusive networks.