I'm always amazed by the amount of issues some users have with their Macs. It's sad really. Meanwhile I have a Mid 2007 iMac built in July of 2007 that is still working flawlessly and has been for over 9 years now. Screen is just as good as it was the day it came out of the box, perhaps a tad bit dimmer if anything. PSU is fine, fans are fine, RAM and SSD were upgraded about 4 years back, runs El Capitan with zero issues, doesn't really run that hot for a Core 2 Duo and low end 128MB ATI GPU. 9 years trouble free.
I feel like expecting nearly a decade out of Macs built today is something that is just not going to happen. But I hope it improves. For what it's worth my Late 2013 rMBP is 100% fine yet we have multiple 2015 5K iMacs freezing and having GPU restarts on a regular basis here at work. One has to wonder...
I also have a 2005 iBook G4 that I was using last night while watching the election results come in and it's still 100% functional with everything as it was the day it shipped. Even the battery, and I was even using it on battery power. Perhaps an anomaly but still amazing. My second G4 is the original 2005 Mac Mini and it too remains 100% functional though it's relegated to iTunes and old game console emulator duty.
Perhaps it's just due to there being significantly more Macs than ever before and more users noticing problems? Hard to say. But I can see that their QC isn't quite what it used to be. My 2015 13" MBA shipped with a dent on the bottom panel right out of the box. I kept it anyway since it's a work computer but still...
