The current legal grounds for taking away citizenship, as you've pointed out, are limited to revocation, and those apply only in cases of fraud by naturalized citizens. As you've rightly pointed out, under the 1947 act, there used to be provisions to take citizenship away from citizens who acted in certain heinous ways.
As we have noted, really it's a function of the rules set out in the Citizenship Act, in terms of what is legally possible. The provisions of the bill propose to amend the Citizenship Act in that way, to make it legally possible once again to take Canadian citizenship away in certain specific circumstances.
I'm not sure if that answers your question. Perhaps if you require clarification, I can add.