Comment by simoncion
I'm not the OP, but I expect VPNs are easier to manage because you don't have to worry about slicing up the very, very limited IPv4 non-public space and puzzling out how to resolve addressing collisions between all of the various networks you have to manage. With IPv6 you can just calculate a /48 ULA prefix and allocate /64s for your VPNs (and every other internal network) out of that. If ever you run out of room, just calculate another /48 and carry on... easy!
This and you can allocate prefix for services. Also you can do layer 3 access control because there is no NAT. Also NAT can get messy when chained. One very practical example is that if I am connected with SSH to a server, and connection is interrupted with a network gear config change for example, when it is back up, SSH will be still connected and might not even notice. With NAT, states can be dropped.