Could you please diagnose my bottleneck?

[TkSilver]

Most non google/non nvidia "flagship" products fall under Tier 2 unless the driver fixes are made to correct a very important issue (like a phone model running way way way too hot). Most manufacturers have little to no incentive to improve the performance of their device outside of the initial launch window where all the reviews are getting pushed out and in most cases making it less desirable to throwaway your old device and buy a new one goes against their best interests.

Google does it because they want to show off the best Android can be since they are more interested in selling the OS then the devices. Nvidia does it because they don't continually update their device and the ones they have released are more for the prestige of having the best graphic solution in X form factor and to sell accessories to their primary product.