Analog sensor nonlinearity near the rails
Correction: range is 0.015V - 4.985V

Close to power supply rails is common for sensors that have been followed with an active linear amplifier before output. Since your sensor outputs a linear voltage, and requires a 5V power supply, it seems that a linear amplifier is likely used.
A sensor that generates its own voltage or current (like a piezo, or a sense coil) and has no amplifier would not likely have this kind of specification.

A linear amplifier includes transistor devices (probably N-channel and P-channel MOSfets) that pull the output voltage down toward ground (zero volts) or up toward the positive supply rail (+5 volts). These devices cannot pull all the way....
An analogy might be raising a weight from a ceiling-mounted pulley with a rope. No matter how hard you pull on the rope, the weight can only rise up to the pulley, and never quite reaches the ceiling. That would be analogous to the +4.985 voltage limit of your sensor not quite reaching the +5V power supply ceiling.