This. Forcing open will lead to restrictive firewalls. Unless ED changes the netcode to a server-centric model (not going to happen), forcing open is not an option.ED is a P2P, so any 'forced' Open-only experiment will mostly just result in people who don't like that to run an app in the background that blocks incoming/outgoing traffic. There has never been such a phase, and there never will be.
What about xbox and playstation players though? They'd suddenly need to pay a subscription to play which would be another no-go.