Apple’s official router, AirMac Extreme, doesn’t have built-in VPN server functionality.
VPN passthrough is supported, so it’s possible to connect via VPN from outside by setting up a VPN server on a PC on the LAN side and doing appropriate port mapping.
I think the policy of placing a router at the core internet part to allow VPN passthrough and setting up a VPN server on the back side is good.
That’s all from the Gemba.