Chosen Solution
I was watching Youtube when this started happening. It’s had some weird graphics issues in the past (horizontal green lines), but this seems different. Is this a GPU issue or a display issue?
My initial thought is display. Especially based on the bands of “normal” in between. These stripes almost certainly align with the cabling inside the display. You can see what I mean a bit in this photo from a 13" model with the bottom bezel (where the MacBook Pro branding is) removed.
The best way to know for sure is to connect it to an external display. Normal video out is a dead ringer for it’s a display issue.
