Not many other sites tried to investigate the issues. Notice the PCMark scores versus the 5433 Note 4, that is something which is just unacceptably bad.
No, they didn't.
But in the end, for a smartphone, what does 25% more
PCMarks really mean, and how much should that weigh in the general impression of a smartphone?
We know PCMark is a whole lot more important that e.g. AnTuTu (which all the non-tech-savvy websites seem to love), but in the end, how much do they
really differ in how they represent end-user experience, when dealing with >1.8GHz CPUs on smartphones?
I'm a very big critic of the M9 myself. I think the device will be HTC's doom, but not because the S810 is a disappointment or the screen lacks in color accuracy.
I think the device is a terrible flagship because HTC decided to keep almost the exact same design for 3 consecutive years. They're too slow at adopting changes from customer feedback.
The black bar saying "HTC" should have been gone a year ago in the M8, or if it
had to stay, they should've kept the capacitive buttons and save screen estate. Speaker design should've been adopted from HTC's own contemporary designs like the HTC Eye or the Nexus 9. They
can make good sounding speakers look a lot better, yet they
chose to go with the same design as the 2-year-old M7. They claim there's no
space to include OIS in the camera, but they have the thickest flagship around. Screen-to-body ratio is the worst amongst all the flagships and they can't even use IP67 certification as an excuse.
While the general industrial design doesn't look bad, their ability to cramp things together keeps being at the same level as the typical 2nd/3rd rate chinese manufacturers like ThL, Jiayu, etc.
BTW, if anything, the S810 being built on 20nm may just have a manufacturing price equivalent to the S801 while offering the performance+features of the S805 + modem. That alone could be a valid reason for the upgrade from the smartphone manufacturers' point of view..
My idea is that Qualcomm isn't really strong on making/marketing tablet chips. I think they originally thought of the S805 as the tablet contemporary to S801, but it got delayed (or they just didn't get much interest from their clients).