The functionality of it is closer to the "Zip+4" with extension used to have a more granular routing of physical mail for USPS.
https://www.canadapost-postescanada.ca/cpc/en/support/articl...
But broadly speaking, nobody knows what their ZIP+4 is, while I imagine that most people in Canada know their postal code by heart.
It is interesting.
To the point that StatCan and other agencies have rules on the number of characters that are collected/disseminated with other data to make sure it's not too identifying:
* https://www.canada.ca/en/government/system/digital-governmen...
* https://www12.statcan.gc.ca/nhs-enm/2011/ref/DQ-QD/guide_2-e...