The emission control has…

The emission control has definitely improved for newer light duty / passenger vehicles, but older vehicles that are still on the road are likely to need more maintenance to keep an appropriate level of emissions. I suggest that testing of light duty vehicles should be kept, but only for older vehicles. I am not an expert and so do not know what would be an appropriate age, but perhaps an analysis of the vehicles that failed their test in the last few years might be useful in determining it. This would reduce the burden on the vast majority of regular drivers while still targeting what are likely to be the worst offenders.

In the UK the emissions test is part of a broader annual test of vehicle safety and roadworthiness called the MOT test, which is required for most vehicles over 3 years old. I am not aware of the rationale or any research related to the different requirements, but with Canada's more extreme conditions I would think that the broader test might bring benefits.