Ya, fair points.
I still think it would be a tough policy to implement though, as far as who has a legitimate use for a big truck and who doesn't. I know plenty of folks who live in rural Ontario who use their trucks as they're intended to be used on a weekly basis, but don't have a "business" need for them.
I definitely get the appeal as an individual voter based on the points you've made, but I think it would be a political loser for any party that pitches it. You'll bleed votes in the 905 for sure, where every second driveway has a F150 or a Tahoe.
North America has definitely gone insane with the size of trucks, I won't argue with that. Fracking keeping gas prices down in the late 2000's and 2010's really supercharged the U.S. truck culture which bleeds across the border. I don't blame anyone for wanting one, but 80% of people could be using something like a Colorado or a Ranger. Or even Ridgeline or the new Ford Maverick - basically a car with a truck bed.
For comparison, here's what a regular everyday truck looks like in Australia: