They're suggesting that readability and "5-second accessibility" are essentially contextual and build on a conceptual language that might be specific to a tool, team, or project.
The novel function that might take "5 seconds to read" for the 20 people contributing to a mature project with a good architecture might nonetheless take 10 minutes for a new hire to decipher because they don't know the local vocabulary (architecture, idioms) and need to trace and interpret things elsewhere in the project and its libraries.
Meanwhile, writing implementations in a way that tried to avoid a local vocabulary altogether might make naive reads easier, but less readable to experienced team member because they're not as concise as they could be.
Your general advice to "make things easily readable" is good advice, but like with writing compelling prose or making accessible graphic design, you need to consider your audience and your choices might look different than the ones somebody else might make.
Go is a board game with simple rules but combinatorial consequences to those rules. Minutes to learn and a lifetime to master.
This is where “simple recursive data structures” can be simple to read but difficult to track and comprehend. An architecture that descends through distinct layers at least has landmarks that the recursive one does not have. If you are not at the root or the leaf you don’t really know where you are, lost in the middle.
The novel function that might take "5 seconds to read" for the 20 people contributing to a mature project with a good architecture might nonetheless take 10 minutes for a new hire to decipher because they don't know the local vocabulary (architecture, idioms) and need to trace and interpret things elsewhere in the project and its libraries.
Meanwhile, writing implementations in a way that tried to avoid a local vocabulary altogether might make naive reads easier, but less readable to experienced team member because they're not as concise as they could be.
Your general advice to "make things easily readable" is good advice, but like with writing compelling prose or making accessible graphic design, you need to consider your audience and your choices might look different than the ones somebody else might make.