In one sense, yes, there's a lot of room in CUSMA for Canada to change how it regulates. The good regulatory practices chapter is meant to enshrine a very specific kind of pro-commerce way of regulating that does push the precautionary principle quite far down the list in terms of priorities.
There are parts of the CUSMA that require Canada, in perpetuity, to regulate in the area of cosmetics, for example, in what they call a risk-based way, so it would be in contrast to a precautionary way in, say Europe, or other jurisdictions, or in a hazard-based way, which can be more protective of public health in other ways.
For the most part, Canada could simply issue a cabinet directive, as it has done every few years now on regulation, changing the way it regulates, so that these other interest groups are brought more into the picture, and so that regulations do a better balance between the commercial interests of companies that will be affected by these rules and the interests of the environment, the animals, the people who are affected by some of the products that get put on the market.