Google just can't seem to catch a break with its second-generation Pixel handsets, as latest reports now claim that the update to Android 8.1 (Oreo) has had a significant negative impact on the devices' fingerprint sensor. Specifically, users are reporting that upon placing their finger on the sensor, their device vibrates to indicate that their fingerprint has been registered by the hardware. However, it then takes as much as a full second or longer than it took prior to the update before the screen actually turns on and the device can be used. That would seem to indicate that the problem is not actually with the fingerprint scanner itself, and is instead a software bug that arrived with Oreo. Meanwhile, a second in time may not initially seem like a big deal but with users checking their devices nearly 100 times per day by some estimates, those who experience the problem could be wasting minutes more on average, just trying to unlock their devices every day. It is also a well-established fact that even small delays can seem overwhelming from the perspective of users when it comes to interacting with a given technology.
With that said, it isn't immediately clear whether the issue affects both the Pixel 2 and Pixel 2 XL or just how widespread the problem is, though the Pixel 2 XL appears to have been in focus of the latest reports. However, both second-generation devices are essentially comprised of the same hardware and run nearly identical software. So it isn't unlikely that the problem is affecting some percentage of both devices. The person who initially reported the problem prompted some other users to claim they're experiencing the same issue and while such development may indicate a large number of affected units, that isn't a given. Bearing that in mind, other users have responded to say that the problem is not just with fingerprint unlocks but also occurs when pressing the power button to unlock the device.
Whether this is a widespread problem or not, Google does appear to be actively investigating the claims. More directly, Googlers have responded to reports and complaints made via the company's support forums, indicating that they are collecting device logs of affected phones. So users who are experiencing problems should probably report them, as it's hard to imagine that unlock delays would remain an issue for very long once the company determines where the issue is coming from and additional reports give Google more to work with.