Because of the tarrif and trade war our local industries will struggle and collapse, there's nothing we can do about that - they were dependent on US trade partners and markets, the Canadian market is much smaller. We have massive productivity issues, there's little chance we'll successfully build our own auto industry.
In the interim buying more from China doesn't really hurt us, and sends a strong signal to the remaining people who care about foreign policy in Washington that there are penalties to treating allies like enemies.
I used to really strongly oppose Chinese expansion and the rise of cheap products getting dumped everywhere - I still do, but I oppose the US admin more; and at least they're stable and clear about what they want