Unlock iPhone via accessibility button press rather than "Slide to Unlock"?
I upgraded the iPhone to iOS 12.4.8.
Now, when I press the Home button on the lock screen, the Passcode entry screen comes up.
If I remove the device's Passcode, clicking the Home button automatically fully unlocks the phone.
This did not work in the previous version of iOS the phone was using earlier today. So it was added sometime in the iOS 10, 11, or 12 timeframe.