The shitty ram thing is especially egregious and was not the industry standard at the time, especially for your flagship phone.

The weird audio issues on multiple devices is also out of the norm.

Current pixel phones are pretty good! But it's clear that for at least the first 4 gens they had some QC and quality of parts issues.

Edit: also to add, it's a basic thing that if your phone is dead dead then you should use wall power to power the circuit to charge the battery. But if you let it sit for a few months, your older pixels will not charge again unless you put in a new battery with some charge, that is definitely out of the norm and is also something that should have been rectified sooner.