Abstract algebraic equations are not closer to biology than the steam engine or clockwork watch.
The latter are at least physical. Gradient descent and inference doesn’t resemble the physical mechanisms that drive neurons at all. Floats and integers aren’t even capable of representing a continuous voltage potential.
There is zero relation between a "neuron" in neural networks and a real neuron. It's entirely marketing. The field of "AI" has always been quick to market their work as magic rather than be open and honest about the reality, which is why we have been through at least 3 AI winters already.