No capital gains on principal residence. It would only come up on things like rental properties, cabins, or any other second property.

There’s also things like of a person has RRSP room and ends up in the edge case where this comes up just once or a few times in their life, they can use that to hold off the income tax until they can claim it at a lower tax bracket. If one isn’t put over by a single sale, (say selling multiple rental properties at retirement) they could spread those sales over multiple years to maximize that first $250k rate.