How Engaging Is An Open Public Discussion If It Costs $20 To Enter?

This is a non-starter of an idea. Not enough people will pay for the site for it to be a "community". I would be surprised / impressed if they are able to get people to use the site for free. We are being flooded with information, and have limited time / attention. This is the real problem that the news media face - they are selling / giving away generic information in the age of the niche. If the news industry had woken up 10 years ago they might have been able to build a platform like Google, but they missed that boat.