IMO they peaked with the Nexus 6 - camera has gotten worse and they make up with it in software or try to. You could and can see this at night or stacked shots in N6 vs pixel 4,5,6.
They bought the best phone hardware and software companies (Motorola and Android) and gutted them both.
They purchased Motorola Mobility for the patent portfolio as essentially a nuclear deterrent against Apple and then sold it to Lenovo. They're doing quite well internationally but haven't been a big brand in the US for a while. Their flagship phones are going to have GrapheneOS as a selling point soon and we'll hopefully be able to expand beyond the high end over the next couple years.
There is really no "they", all Nexus phones weren't made by Google. Hence why, the 5X aside, everyone has nice memories of them.
...have you tried any of the cameras from the last 5 years or just the pixel 6? My 11 pro's cameras are by far the best cameras I've ever used on a smartphone, my previous iPhone included.
Google also bought the HTC hardware folks for the Pixel phones - see https://www.engadget.com/2017-09-20-google-buys-htc-pixel-te...
Nexus 4-6 were manufactured by LG IIRC.