"Brute force" would be trying random weights and keeping the best performing model. Backpropagation is compute-intensive but I wouldn't call it "brute force".
> You determine the weights via brute force. Simply running a large amount of data where you have the input as well as the correct output
Brute force just means guessing all possible combinations. A dataset containing most human knowledge is about as brute force as you can get.I'm fairly sure that Alpha Zero data is generated by Alpha Zero. But it's not an LLM.
The sampling stage of Evolution Strategies at least bears a resemblance but even that is still a strategic gradient descent algorithm. Meanwhile backprop is about as far from brute force as you can get.