Indeed. This is how it works now. Before selling or giving any phone away, the owner MUST delete all content and settings. This not only deletes the phone's contents, but also removes the original owner's Apple ID and password from the firmware and removes the phone from their account. It prevents phones that have been stolen from being reactivated by anyone besides the original owner.
This is misinformation.. Wiping the phone does not turn off activation lock.. You need to turn off find my phone prior to resetting it... The activation lock is not on the phone so even a DFU restore will not remove it..
Here is how it works.. When you turn on find my phone it sets an activation lock on apples servers.. Unless you disable find my phone for that device.. Apple will not activate the phone without your apple ID and password.
Restoring the device at ANY level does not turn off find my phone.. If you restore update or reset all content you will still need an apple id to activate the phone.. It is all serverside.
If you are selling your phone.. You first need to disable find my phone, it will ask for your password, then you reset all settings snd content.
If you forget to disable find my phone.. You can disable it remotly without giving the buyer your info.. Just open your find phone app on any device or icloud.com and remove the device in question from there
So basically if your phone has been activation locked.. it is on apples servers and you need the apple id that it was locked with to activate fhe phone... If you dont havd that apple ID or know anyone who does... You are SOL... But if this is the case your probably using a stollen device.