Does auto leveling result in sheared prints?
Using automatic bed leveling assists you in getting the print to stick better to the build platform as a result of the print head following the un-uniform geometry or tilt of the build plate. 

In, e.g. Marlin Firmware, the bed level correction is fading out over a predefined distance, this is determined by the constant #define ENABLE_LEVELING_FADE_HEIGHT in the printer firmware Configuration.h file  and the height can be set with M420 Z&lt;height&gt; (see here). 


M420 S1  ; Enable compensation using current grid/mesh
M420 Z10 ; Gradually reduce compensation until Z=10



Yes, a cube will not be perfectly cubic, that is why even with auto bed leveling you need to provide a bed as level as possible, it only should correct for very small deviations.

When the print is smaller than the fade out height, you would indeed get a sheared print, if larger, then the top of the print would be level with respect to the reference plane (this is the level of the x-y plane, basically the level of the hot end carriage). Note that that still can be skew if the printer is improperly calibrated (e.g. when using 2 Z steppers or misalignment of the height on either side).