Is outlined here: Taxing the Wealthy Sounds Easy. It’s Not. – The New York Times.
It’s worth a read. It’s thoughtful, even if you may not agree with it. Also, just because something is not easy does not mean do not attempt it.
Taxing drives behaviour. My thought is drive behaviour in the right direction. Tell affluent people to use their wealth in directed ways that improve our society or tax them so that it can be done. If they disagree, then it is time to make explicit the social contracts in place and ask what has to be changed to make for a better society. Because for most societies in the world, including Canada’s, the social contract can be a lot better.