> Party leaders are picked internally by party members via leadership races
Correct.
> not by the general public. This is good because the leader is selected not by "Low Information Voters" […] but by people who have gone through a qualification filter
Not really. It's true that only party members can vote, but the only requirements to be a party member are to be a Canadian citizen and to not be a member of another party [0] [1], which is effectively the exact same requirements that the US primaries have.
I think the difference is that in the US all it takes is one pied piper because voters can vote directly to elect him president. In Canada, the pied piper is going to need more pied pipers under him to be elected as MPs.