I think I understand your question.
The Supreme Court rendered its decision in R. v Brown just a few months ago. The Court believed that there might be circumstances in which a person would be able to establish that they were in a state of self‑induced extreme intoxication akin to automatism, but that they were not able to foresee that they might fall into that state.
Section 33.1 doesn't create the defence. It doesn't define the defence or the process for invoking it. Therefore, section 33.1 doesn't directly affect the availability of the defence. Rather, it creates a rule of criminal liability and defines the elements of culpability.
Instead, the question is whether or not the elements of culpability in section 33.1 are constitutional. As the Minister said, it was the Supreme Court that suggested this option as constitutional.