Safe mode, temporarily disables third party user installed apps, to see if the issue is related to user installed apps or not. Third party user installed apps may sometimes cause graphics corruption (very rare, but it does happen).
If normal restarting of phone fixes it temporarily, or the phone perfectly runs till Samsung logo and then graphics corrupt after that screen, it's software issue. It happens to me sometimes (while messing with system files).
But if the issue is at boot logo too, its hardware issue, maybe display strip or on board connector problem or even touch panel.
But it's better to take it to Samsung Service Centre, they check software issues (graphics corruption) first before jumping for LCD replacement, unlike phone repairing shops.
To me, it's looks more of a software or display strip or on board connector issue. Damaged LCDs have permanent issues and they make touch unresponsive too, but that display test #0# passed, so LCD itself is working great.
