It's not a good choice. The Canadian government still doesn't understand the internet. There should be no obligatory private intermediaries between a citizen and the government no matter online or offline.
It should provide an online identity service, just like it already provides offline government-issued IDs (e.g. passports) without involving banks or other private institutions.
> You can also create a stand-alone account with the CRA if you wish.
You can't reuse the CRA login with all other government services. I'm talking about a single identity provider accepted by any government service, like a driver's license or a health card.
* https://www.canada.ca/en/revenue-agency/services/e-services/...
* https://www.canada.ca/en/revenue-agency/services/e-services/...
* https://verified.me/government-sign-in-by-verified-me/
You can also create a stand-alone account with the CRA if you wish. Other federal agencies use the 'partner' system as well.
It's basically SAML.