The effort to understand how the brain works on an algorithmic level is alive and well.
This endeavor is primarily known as “computational neuroscience” and is a separate field of study from deep learning.
It is common for researchers to move back and forth between both fields.
The field of deep learning is primarily concerned with how to build computer systems that are able to successfully solve tasks requiring intelligence, while the field of computational neuroscience is primarily concerned with building more accurate models of how the brain actually works.