Not sure since I don’t use a VPN. If they assigned a unique public IP per user they could just forward every incoming connection to the user’s PC.
If they don’t they need to setup some port forwarding rules.
If openVPN leaks IPs that’s surely a bug, if it’s specific to v6 you can’t use openVPN and IPv6 till the bug is fixed
Port forwarding is necessary due to NAT not firewalls.
It’s not that your router blocks new incoming connections at port X, it’s that it does not know which local client it’s meant for, since it’s addressed to the public IP that is held by your router.
With IP6 it’s lan client also gets assigned a public IP6 address (as there are plenty) and so the router receives a connection addressed to a Lan client and knows where to route it.
Its an action game with RPG like stst systems.
So non RPGs are better RPGs? You don’t have to like RPGs.
They most certainly have this covered in ToS. IP law is not about actual creators’ rights.