Here are the reasons I think this is the best system for the majority of content creators in the professional space:

Most of the popular systems now make recording into the camera from one or two wireless mic transmitters relatively simple.

if you had to sum up the difference between the two similar looking mics it would come down to these two features:

The Wireless Go II can record audio as well as transmit audio, and works with up to two microphones.

The Wireless ME can record up to 3 microphones, but has no onboard recording option.