Fast.ai's courses start at a high level with working code right off the bat. Then they break it down and show you how the parts work. It's much more motivating when you don't have to wait a long time to see any results. [Edit: and you know you're going to get something good instead of putting a lot of work in and getting something mediocre or plain not working.]

See this paragraph in the article: https://www.zerotosingularity.com/blog/fast-ai-part-1-course...

I guess titles are meant to attract and provoke a little at the same time...

Fast.ai uses a top-down approach, allowing students to get awesome results with a minimal set of instructions, and start to dig deeper from there. If you look at the takeaways from the first lesson, you can see it's more than just three lines of Python and you're done, It's a solid and fresh approach to learn some actual practical deep learning.

Additionally, it kind of depends on what you want to do, we are all using things other people built, depending on the level of abstraction we care for or are willing to deal with...