In the ruling which is outlined below one of the key facts in the decision seems to be  that the project is not Owned, controlled, leased or operated by a person operating a federal railway

from their site

The Canadian Transportation Agency has ruled that the proposed construction and operation of a passenger rail service between Toronto’s Union Station and Lester B. Pearson International Airport does not fall under federal jurisdiction. As a result, the project’s proponent, Union-Pearson AirLink Group (UPAG), will not be required to obtain an Agency-issued certificate of fitness, nor will it have to seek federal approvals under the Canada Transportation Act and the Canadian Environmental Assessment Act for the proposed railway line.

In making its decision, the Agency found that the new passenger rail service would not be functionally integrated with the operations of the federally-regulated Greater Toronto Airports Authority (GTAA), which operates Pearson airport. It also noted that the proposed facilities would not be an essential or integral part of the GTAA’s activities.

The Agency’s decision of the jurisdictional status of UPAG’s project is based on evidence provided by the applicant, and could be revisited should the project not be developed as presented.

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