As a user, I also think it's fantastic, from a design and usability perspective. (I can't speak for accessibility.)
It's snappy, clean, and not at all bloated. I dread the day that some MBA introduces Silicon Valley KPI reviews and perf metrics to the government, leading to some middle-level engineer replacing that simple, clean, bell-and-whistle-free design with some built-for-promo bloated garbage.
https://www.canada.ca/en/government/about/design-system.html