Hello! We are excited to announce Steam Families is now available for all users. Steam Families is a collection of new and existing family-related features. It replaces both Steam Family Sharing and Steam Family View, giving you a single location to manage which games your family can access and when they can play. Create a Steam Family To get started, you can create a Steam Family and then invite up to 5 family members.
As much as i don’t really like this there would have been a loophole where you use fake temporary family members to continue cheating.
Back in the day some games also banned your homes external ip address which would have a similar effect.