I have a QLED (QE50Q60AAUXXU) which is less than 2 years old. A few weeks ago a horizontal line appeared on the screen and over the last couple of weeks, more and more lines have started to appear.
I've not contacted Samsung as yet, but I'm pretty sure I'll just get the usual "sorry but it's out of warranty".
For a TV that is not very old, it's not a good look for Samsung.
Spoke to Samsung and as predicted, they don't really care as long as their TV's last at least 12 months. If you get a duff set, it's just tough once that 366th day rolls by.
Maybe time to try a different brand.......