As long as the facts being discussed are accurate and the criticism doesn't attempt to misrepresent or distort of the truth, it's hardly an attack ad or what anyone could call an "unfair criticism" of Trudeau. If it looks like a duck; walks like a duck; and quacks like a duck; it's not unreasonable to say and suggest that's exactly what it is.
As for Justin going up the down escalator it hasn't gone unaddressed by the NDP candidate behind this blilliant ad that needs to be spread far and wide...
https://www.youtube.com/watch?v=A0Ax1_2fwd8