[Saris]

I always thought part of the advantage of IPv6 was that each device is accessible to the internet for functionality of things that normally would need port forwarding, without requiring any config on your gateway.

Devices have their own firewalls already, and most people will be on public WiFi at some point too where even IPv4 would be exposed to random people.

I'm more concerned that the Synology NAS mentioned just exposes itself to the global internet by default from the sounds of it. Surely it should deny access except from internet IPv6 subnets until specifically told otherwise?