A 3D web map allows for more versatility in data visualization than 2D web maps. If this lab's dataset was visualized in 2D, then a sequential color coding of the points would only show which points are grouped together by a range of values rather than visualizing each point's specific value. By mapping in 3D, the color coding is still retained but the viewer can also see the individual magnitudes of each point value. Mapping in 3D would thus be more appropriate than 2D web mapping when trying to communicate the magnitudes of individual data values in addition to the spatial distributions.
Another scenario where 3D web maps would be more appropriate than 2D web maps is mapping elevation. Human eyes can have difficulty interpreting elevation from above, and this is why 2D maps often try to represent elevation with contour lines or gradients. With a 3D map, viewers can better understand elevation because the data is visualized in a more relatable way that's similar to the traditional, ground-observing human experience. This is exemplified in the "Major River Basins of South Carolina" map (Source: South Carolina Department of Natural Resources). From above, it's difficult to fully understand elevation differences. When viewed from the side in 3D, the hills and valleys become much more clear.