I think of a membership site as being a product.
Different peoeple use the platform in different ways.
Some use it to refer to the people who follow you via email and social media. They are primarily interested in gaining an audience who want to buy their book or whatever it is.
In UK politics a platform is the candidates’s message or the group of policies that they intend to promote if elected.
From what I understand Sean is using it to mean the site (i.e. online space) that you use to express yourself so that those who are interested in what you have to offer gather around you.
I am reminded of a story told by Winston Churchill when the relationship between the US and UK delegations at a conference broke down. They had similar aims and no one could quite understand what had happened. Then a junior member of one team discovered that the same set of words meant totally opposite things to each delegation. Change the idiom “to table a motion” to something else that explained the proposed action more clearly and they were friends again.
There are times when it is as important to understand the definition of a word as it is the word itself.
God's Lily is "a voice for those frustrated by the slow progress towards a fair society where the needs of the weakest are met in a way that it strengthens them rather than weakens them further" . If that includes you then hop on over and have a look around. If you like what you see it would be a good idea to sign up to receive our blog broadcasts. Oh and you will get a couple of pdf files that explain the what and why behind the site when