They get credit because they have been working formally under a regulatory co-operation arrangement with their counterpart. In other words, that reduction is really the result of work that this regulator has been doing. Generally speaking, formal regulatory co-operation initiatives have regulators work together to develop work plans. Those work plans are meant to reduce burden on business in both jurisdictions.
The rationale is that the Canadian regulator is not doing nothing in this scenario. They are actively working with their partner in the U.S., and together they have come up with a regulatory co-operation work plan, the output of which may just require a change in one jurisdiction, but that still reduces burden here at home, and it is the result of a co-operative arrangement.