I mean, sometimes, it's justified. Should a negative review about a wireless-charging bug in a phone stick around once the manufacturer pushes out an update to the firmware that makes the bug go away?

This is why app stores only show reviews/scores for the current version of the app. There's no such thing as "versions" of a product, though. (Or, well, there are product revisions with distinct UPC codes, but an OTA firmware update doesn't qualify as one, and yet should be a new "version" for the purposes of reviews.)