People could discuss cognitive biases in a really stupid and irrational way that would make it unproductive?

The way she discussed it wasn't productive. There also the general field of Gender studies. As a field it doesn't encourage open and data driven debate about the subject. When you start a discussion with saying that your opponent holds their position because of implicit bias that doesn't tend to be a discussion where it's easy to focus on rational argument.

Yeah?

The problem is that you are making claims that are wrong. It wasn't a discussion of how implicit bias works. If you want to analyse claims about a debate it's useful to stay with the facts.

You seem to making a black or white argument that Clinton's comment isn't useful because it's not that useful

No. Focusing a discussion on implicit bias means to not focus the discussion on "How can we solve this problem?" It's a rhetoric strategy to signal concern about Black Lives Matter while at the same time not having to actually discuss policy solutions to the problems.

There's also a good chance that a conservative person who hears the debate is harder to educate about the concept of implicit bias after listening the debate.

The intellectual toolkit of Gender studies with includes asserting that the opponent is driven by implicit bias and privilege is not useful for having rational discussions. The communities that engage in that toolkit generally don't want to let data decide.

The also don't ask the obvious questions such as whether the fact that more Whites get killed than Asians is also due to implicit bias. That a very straightforward question if you look at the data and want to use implicit bias as a cognitive tool for explaining the data of police killers.