Note on the definition of sympathy. One can have sympathy for where someone’s coming from but completely disagree and be opposed to an action it inspires them to take.

You claimed that the survey showed that they "support" the protests. The question asked only if people "sympathize" with the "frustration" of the convoy. That is a very low barrier, easy yes, given that a strong majority of Canada is tired of mandates. Indeed, the question went so far as adding "may not support the protest" to specifically delimit.

Canadians are very against this protest. If they simply parked some trucks and hung some signs, whatever. Once they were blasting horns 24/7, and then when that didn't work (given that the overwhelming majority of "truckers" are not with their cause and continued working) blocking international borders, the Canadian public turned dramatically against this petulant outrage. Having a bunch of Americans cheering it on, financing it, and even trying to join in has made it a cause that most Canadians find outright treasonous now.