While early versions of NAD83 and WGS84 (in 1986/1987) were virtually identical, they have diverged significantly. The North American Plate moves relative to the global reference frame. Because NAD83 is 'plate-fixed', coordinates on the ground remain relatively stable over time. WGS84, being a dynamic global frame, moves with the earth's general rotation and plate mechanics.
The Current realization: G1762
If you take a raw RTK GPS shot today (which resolves natively to WGS84 or an ITRF equivalent) and plot it natively in a CAD system expecting NAD83(2011), the point will be shifted roughly 1-2 meters. Official NGS transformation tools must be used to execute a 14-parameter Helmert transformation to shift the time-dependent WGS84 coordinates into the fixed NAD83 frame.