Apparently CRA will still apply the proposed change. Even Poilievre hasn’t committed to cancelling it:

Trudeau’s main political rival, Conservative Leader Pierre Poilievre, has said he would review the tax hike if elected, but hasn’t committed to scrapping the measure if it became law. The Conservatives are about 20 points ahead of the Liberals in most polls.

Then again, if they don’t reintroduce it to Parliament, I assume CRA will just stop collecting it. And potentially issue refunds. 😂