After Pixel 6 was criticized because of the dreadful fingerprint scanner, this time, with the budget device, Google decide to not use the sensor anymore. Therefore, you have a reliable fingerprint scanner on a Pixel 6a.
Google’s Hardware Team Lead, Rock Osterloh, has confirmed to Android Authority, that they are not using the same fingerprint sensor from the Pixel 6 series inside the Pixel 6a. But chances are high that it might not be as bad as the Pixel 6 but not good as any other device. But after a lot of criticism, Google might have just prioritized the issue with the sensor for the time being.
Since Google at least considered the issue and switched the sensor for the better, it might come to the point that Google will go with a far better sensor with the Pixel 7 this time.
Source: Android Authority
Also, read: Pixel 6a: Scheduled for sale!