Hello, I have the same laptop, same model, and cannot figure out what's happening.
I have exactly the same problem, can someone from Apple can do something?
Definitely, it cannot be a coincidence that the following facts are likely to happen to so many people:
- this happens right after two years of warranty
- this typically happens on macbook pro 16 and 17
- people complaining about it didn't have accidental damage (are we all liars?)
In my case, i personally reported this summer to Apple Store a damaged yellow charge cable, due to probable overheating, that seems to be similar to the problem of these horizontal lines/artifacts.
They replaced my cable, without finding any anomaly in their diagnosis. 3 months later this problem, still a coincidence, guys, really???
I've spent the last three days with Apple Support trying to reboot the whole computer, a lot of time spent on doing a backup with time machine, updating to Big Sur, they tried to consider me guilty for any superficial stuff, like "you have a lot of garbage in "Other" section in archive", or "well, you probably keep the monitor on too much". WTF?!?!??!
I spent 2000 euros for a computer, i don't expect to keep it turned on for a week, but does it really depend on keeping the monitor on for 3 or 4 hours? Uh?
I am so frustrated, today is about 2 years and 1 month that i have this computer and of course, this kind of stuff happens when important things have to be done.
In this case i need my computer to work and cannot wait for a month to be repaired, because of course i bought it from MediaWorld, and after the first year i should contact them.
But, APPLE, if you have thousands of people with the same problem, why don't you do anything?