There's no need to 'delete wealth' or anything like that - assets are assets and will still have value, although a crash would see them return to something approaching their real value rather than the inflated values that we've created over the last 20 or so years. That means that anyone who's over-leveraged (and there are a lot) could run into negative equity, which will have knock on effects due to the bad debt that it creates. We could've normalised monetary policy 10 years ago and dealt with the fallout, but as we've held out for so long the fall is now going to be much more painful.