Ok, brah, you started your post with a baldface lie. You did not purchase a "brand new" device. You went to eBay. Some shady reseller gave you what's known as "new old stock". A still-sealed White Album first press is not "brand new" because it's 56 years old.
The Pixel line is up to model 9 now; my 8 is still fresh. Those are the "brand new" and supported devices. Get real.
The package was sealed, the device (according to ADB output has no charging cycles) and was obviously never in use. That's what I would call brand new.... But if that's the wrong term and "new old stock" is what it should be called, I wouldn't disagree.
Doesn't matter though, as it's still a perfectly fine device that cannot be updated even though that's only limited because of Verizon's policy.
Since I already updated three other non-verizon Pixel-2s it was surprising to experience locked-down-for-no-obvious-reason devices that can no longer be put to good use.
Seems like a nice idea to put these devices to good use by unlocking their bootloader and installing a custom ROM image such as Lineage OS.
Except... when you are dealing with Verizon devices which -- for reasons unknown -- sinply cannot be unlocked.