I guess at the time this course was recorded these didn’t exist or Grant didn’t know about them, but here’s a video of future Grant himself talking about some of the options available for retopology, both automatic and manual:
TL;DR:
If you are in a hurry and on the cheap you’d be better off using Quadriflow (you can within Blender) or Instant meshes, but of course manual topology is still the best if you have the time and knowledge.
