Responsibility to users?

What responsibility do the providers of a platform have to the communities that use that platform? The example below is slightly different because it was a commercial company, not a cultural heritage organisation, but it raises interesting issues.

Discussing Disney's deletion of their Virtual Magic Kingdom in Considering New Ethics in Virtual Communities and Cultures, radical trust says:

Let's not hide behind the word "virtual". Connections made in online communities are real. When considering the totality of socially transmitted behaviour patterns – arts, beliefs, institutions and all other products of human work, thought and emotion – we are well beyond the basic definitions of community and entering the realm of culture. Although Disney owned the virtual-estate, do they have the ethical right to disintegrate the culture within?

As online communities continue to aid and develop human connections, do we need to start considering the ethical responsibilities of the platform controllers to maintain these cultures?