Solving problems is the purpose and focus.

How to solve problems?

The simple, direct, and effective method is good one method sometimes, not all time. For example, use very complicated method to obfuscate code in order to increase the difficulty of cracking, and there are many environments to use complicated code or methods.

So one is the purpose, one is the method.

Do not think "Lower Cognitive Load" is the purpose.

"Lower Cognitive load" is just the by-product sometimes, not the purpose.