Looking in the white pages for people’s details was the done thing in years previous to the late 90s and then came along the internet. If it wasn’t a Google search or a quick lookup on Facebook usually did the trick pre-data protection and GDPR etc.
Facebook searches were as powerful as Hull white pages use to be.
You could once add a mobile phone number to the search on Facebook and then find more or less everything about the person whose number it belonged to.
This is no a removed feature and you can no longer search a mobile phone number to reverse lookup a person.