Psycowave
There's no real "best practice," it just depends on a person's use case and preferences.
Similar to how, in Linux for example, one's main User should not have unlimited sudo permissions, it can be considered a good idea to have your daily driver User on GoS inside of a secondary user. Since certain core settings for the OS can only be accessed from the Owner profile, using a secondary User can limit exposure to these settings if, for instance, your phone is snatched out of your hand while inside a secondary user.