A Trump-like actor in Canada would do far less damage than in USA. There is no position they could held that would give them the power to do lot of damage. The Queen (nowaday King) has no power. If they tried to use it's constitutional powers as written they would be laughed out. The Governor General, who may act on behalf of the Queen would be laughed out too if they tried to take any decision. The Prime Minister seems all powerful but they are one motion from the House of Common from being overthrown. When one's become POTUS, they are basically POTUS until the end of their term. The exception is impeachment which is a very complicated process that never worked. In Canada, the House of Common can simply vote the Prime Minister out. The Prime Minister is very powerful, I agree, but only as long as they behave.