I don't know a single person personally who owned pixel or nexus and never needed to get their mobile serviced because of fault with motherboard or something. It's not normal. Not just electronics but mobile bodies developed cracks without any fall or anything. Jerryrig videos show badly made are google phones.
Between me and friends, we have more than dozen chinese and samsung phones and none of them ever needed any visit to service center apart from the broken display or battery change.
Also please can someone explain to me why pixel are considered stock? I must be blind or something. Pixel looks like a skin to me. It implements google's own 'material you' philosophy. Why is it stock? Do pixel feature exist in other stock androids?
Most people don't realise how barebones AOSP is, the actual stock Android. LineageOS comes close to it. Pixel is just Google's implementation and people think it is stock because it is from Google. It has more proprietary Google software than other Android devices. That is also the reason Google messes up Pixel so often, they don't really have an incentive to provide a better experience compared to others.
Fact that they can't even match Samsung's update period with their own SoC is telling. They just don't want to do much more to be regarded as a hardware company.
The real benefit would be the specific camera changes and the fact that the device is the most easy to use for custom ROMs due to the kernel code being readily available compared to a lot of manufacturers who do nothing to help.
Well, for most 99% of the people using Android, Google IS Android. The geeks who tinker with ROMs and kernels are extremely limited. I used it to do it when I was a student and a bachelor. Job, responsibilities, children etc just wants you to use something which works.
Nexus was what Google wanted to show the world what can be done with Android. It used to a cheap phone, great for the price, but with major issues.
Pixel lineup is supposed to be Google's answer to iPhone. You can see the continuous iterations throughout the years.
They provided ample incentives for early adopters to switch - no bloatware, unlimited OG quality photo backup, then 3 years OG quality backup etc.
As phones like Mi, Realme, Vivo ballooned (including earlier versions of TouchWiz), there was a gap in the market for barebones devices - and while Android One' program had a few takers, eventually I'm guessing the OEMs lost interest (and incentive).
I still have great memories of Nexus 6P - one of the first phones with (for that time) insane low light performance. You couldn't get that with ANY phone camera. It was magical. Of course, Huawei had build issues. Pixel 1 was weird with HTC manufacturing it, again lots of issues.
P2/XL was more refined, with LG's help. My only reason for not continuing it was limited RAM, which caused a lot of slowdowns in today's time. Else I absolutely love the phone.
4a (for it's price), to me, is love. The matte screen, excellent one handed ergonomics, useful AI powered Pixel launcher, the tried and tested camera - do remember Google really did a lot, LOOOOOOOT of enhancements for computational photography under Marc Levoy. And much of it has been released for free.
Who can forget the absolute insane night mode launched overnight by Google, or the bonkers astrophotography mode !? And again, it tells something when a 6 year old sensor holds its place with many flagships just because of how damn optimised it is with Google's software.
I think the recent phones are a small step for Google to really get into controlled hardware - they're doing chips with Samsung, and maybe it's just a start (or maybe they'll abandon it like many of their projects).
But all in all, there's no doubt the the Nexuses and Android Ones and Pixels have played a major part in shaping the smartphone market we know now.
Edit: Also, from what I think, Google really does not see most other phones as competitors. It's just competing with iPhone SE via A lineup, and we clearly know how much of a mess SE is. I wish the Pro models were better priced - US clearly gets tons of incentives when purchasing through Google or carriers. For RoW, it's bad pricing.