Don't forget that the majority of users that do not experience problems never voice that. The silent majority usually stays silent. Some of the voiced problems here are questions of taste, like a fingerprint scanner not being fast enough (we can talk about hundreds of a second here, depending on the specific need of the person that has a direct point of reference that you might not have), or people hating on a phone that has a power button over the volume buttons (never bothered me for example), or people calling this was cheaply made, which I would call a joke. I've held IPhones, Galaxys, Pixels and other phones in my hand and - by comparison - this is the first Pixel with decent gap sizes (chassie - display). The exterior finish on the aluminium is without flaw. The display fits nicely into the chassie. That's what I call high quality. But that's just my opinion and taste.
If I had to make a comparison, I'd call the Pixel 6 Pro on par with Samsungs build quality, even though it falls behind Apples (flagship), like every non-Apple phone does. Their gap sizes between their stainless steel chassie and display still reigns supreme. Every edge there, well, just fits perfectly. It's that finish that is sorta present on the Pixel 6 Pro, but only sorta - which is still more than most other flagship phones can offer.
There is one hardware quality critic point that was voiced more than once and that is a gap between chassie/display and the top speaker. For some strange reason, I can't replicate that. I have no visible gap there. Maybe I am not looking the right way, maybe it is indeed a QA problem. Be sure to check that.
I'd say the only few serious problems as of now are
1. Random reboots
2. Yellowish tint (reported by several people, even though I personally e.g. do not have that problem)
3. Network connection
4. Throttle/heat after prolonged usage
At least three of those should be easily fixable by software, maybe even all of them. But be sure to check your phone, Google is afterall known for making phones with more than one hardware based problem.