Strange Arduino Serial Behavior
As to why this happens: connecting to the Arduino with the built in USB port would wipe the display because the Arduino would reset and re-initiate the display initialization routine. The spike in current was actually the initialization signal. In the bare minimum sketch the signal going high, low, then back high was again due to the Arduino resetting.
The solution I'm going with is just changing how I connect to my Arduino with python by adding dsrdtr = 1 to my serial declaration. I tested this and my Arduino no longer resets, and uploading sketches is not impacted.
# Python 3.7.5
import serial
ser = serial.Serial('COM4', 115200, timeout=0, parity=serial.PARITY_NONE,
                   rtscts=1, dsrdtr = 1)