Ah looks like I misread the wikipedia article on the topic, you're right about him not being able to suspend civil rights. I'll correct that.
I didn't keep up with the farmer's protests too closely, but I do recall that at the time there were reports that the govt was having trouble distributing aid in the midst of a big wave of the delta variant in part due to the blocking of roads and trains by the protests (although of course it wouldn't be surprising if that was just blame shifting), going off of Wikipedia however, it does look like several routes to the capital were blocked for a while, along with some news outlets reporting up to ~$7B in economic loss due to associated supply chain disruptions: https://economictimes.indiatimes.com/news/economy/indicators...
I personally just find it disappointing that Trudeau seemingly hasn't even tried to talk things out, so invoking this act feels pretty excessive considering how egregious the circumstances were in previous uses. Regardless of whether or not he's willing to compromise (or if the truckers can even be reasoned with), I feel that this act should have been a measure of absolute last resort.