https://www.cnet.com/news/pixel-3-phones-arent-selling-and-its-probably-verizons-fault-google/

There might be a few reasons for this. First, times are tough across the board. The smartphone market has been slowing down. Apple just announced that it sold fewer iPhones than it did a year ago. People are keeping their phones longer between upgrades, and prices are skyrocketing year over year. New phones are entering the market, like T-Mobile's "premium affordable" OnePlus 6T, and buyers may be holding their collective breath to see how foldable phones and 5G networks pan out in 2019. (Hint: not too great so far.)

But for the Pixel phones in particular, Verizon's exclusive backing might be almost as much of a hindrance in getting the word out as it is a benefit. Verizon is the US' largest carrier, which gives the Pixel the advantage of being discovered when buyers walk into a shop or peruse the carrier's website.