When logging into a device for the first time either by email or link function it defaults to the main user without requesting pin even if you have a pin set (when using local user accounts). It would be ideal to immediately go to the local user list and show all users when logging in for the first time. I will give kids access on a device, computer etc and have to then goto change user after logging in to stop them seeing the unrestricted content and then the user list will appear moving forward which forces the pin.
It especially happens on tablets, smart tvs, xbox etc.
When using the link feature it would be especially great as you usually do that unsupervised and have to navigate to it.