There are plenty of good reasons to buy a Pixel, but for many, it's the unlockable bootloader that's most appealing. Imagine the disappointment when some Pixel 2 devices from the Google Store showed up without an unlockable bootloader. Google seems to have gotten right to work on the bug, and it's now fixed.

Having an unlockable bootloader means you can flash whatever you want to the phone. This is an option for all Pixel (and Nexus) phones, except for the ones sold by Verizon. On phones affected by the bug (only the smaller Pixel 2), the OEM unlocking option in developers settings was grayed out. So, people were buying the Pixel 2 from Google, but the bootloader was locked down like a Verizon phone.

According to the issue tracker, this problem has been fixed. All you need to do is factory reset the device and make sure you're connected to the internet during setup. The OEM unlock toggle should be functional after that. A factory reset might seem like an annoyance just to fix a bug, but unlocking the bootloader factory resets the device anyway. A number of users have replied to say the issue is solved, so go forth and unlock.

Source: Issue Tracker