Some reminders:
Polls do not reflect the odds of election outcomes. They reflect prospective voters' preferences subject to a margin of error.
Contrary to popular opinion, in the 2016 U.S. election the polls ranged from fairly to remarkably accurate.
Overall, the popular vote fairly closely matched the pre-election polls, except that both Clinton and Trump ended up with slightly higher percentages of the vote than the polls reflected (reflecting that undecided and votes for other candidates, as measured in polling, ended up as votes for Clinton and Trump). Close to what was reflected in the polls, Clinton won the popular vote (by nearly three million votes total). The outcome was well within the margin of error in many (if not most) of the more reliable polls conducted within the last week prior to the election.
The problem was that many people made wildly unfounded predictions based on those polls, and otherwise many misunderstood what even reasonable predictions meant.
Wildly unfounded predictions: There were indeed some sources forecasting a ninety percent probability that Clinton would win the election. As the Nate Silver site often emphasized, such odds were grossly unsupported by either the polls or any other information. Clinton rarely was shown to be leading in the polls by more than slightly above the margin of error. That did not support a ninety percent probability she would win.
Misunderstanding what reasonable predictions meant: Nate Silver's website gave virtually two to one odds favouring Clinton on November 5, just a couple days before the election, and those odds increased to around three to one by the eve of the election. Many people terribly misunderstood those odds. For some strange quirk of how brains work, it seems there was a tendency to believe that such odds were, essentially, a sure bet. They were far from it.
Take the odds Nate Silver gave on November 5, 2016 (election was November 8), basically two to one (slightly less than 66 percent odds Clinton would win, slightly better than 34 percent odds Trump would win). The odds of Clinton winning were roughly equivalent to surviving Russian Roulette using a six-shooter with TWO rounds loaded (not just one, but two). That is NOT a bet anyone I know would take, not even if they could win a great deal of money. Yet the general consensus, somehow, was that such odds were equivalent to a sure bet.
More than a few commentators posited, after the election, that Nate Silver got it wrong. He didn't. He provided good information and insight. A lot of stupid people interpreted the information erroneously. That appears to be a tendency in that S-hole country part of the world these days. Fortunately a lot of not-so-stupid people are resisting. The outcome of that conflict remains to be seen. However, the odds favouring stupidity just improved given the U.S. DOJ appeasement of blatantly abusive demands from the WH. Sad.
Relevance to 2019 Federal Election in Canada and prospect of major changes to Citizenship Requirements:
Well, many of us can begin voting in an important Provincial election this week. Doug Ford could be elected, and is favoured to be elected, Ontario's next premier. (Pausing to get past a gag reflex.) Actual outcome remains to be seen. Foreshadowing? While there are many issues in this election particular to Ontario politics, just the fact that Ford is the conservative candidate looms ominously. A few months ago I had no idea there was a chance he would become the Ontario PC leader and candidate. I doubt I was alone. Whaaa happened?
STUFF HAPPENS.
Trying to give percentage probabilities on the outcome of a Canadian election more than a year from now is nonsense.
Consider Nate Silver's probabilities in the U.S. 2016 election (he is clearly the among the best handicappers in the biz, which is different from those offering definitive predictions). In just slightly more than one week from July 30th to August 8, his probabilities went from slightly better odds of Trump winning (as of July 30) to 87% odds Clinton would win (as of August 8). Such probabilities swing wildly.
Handicapping the 2019 Canadian Federal election is even more difficult and subject to variation since we do not have anywhere near the amount of polling data that was available in the U.S. election cycle.
Even if there is a Conservative Party majority government elected in 2019:
Again, we have no idea what the odds are that the Conservative Party will form the government after the 2019 elections, let alone have a majority government.
We can safely forecast that even if the Conservative Party forms the government but does not have a majority, there will be no major changes to the requirements for citizenship adopted during that government's term. 100% forecasts tend to be foolish, but this one comes close. Major changes are not likely even if there is a Conservative Party government, if it is NOT a majority government.
What if the Conservative Party forms the government with a majority? This is far more difficult to forecast. The odds of some significant changes increase some. But forecasting those odds, let alone predicting what the actual changes might be, is largely wild guessing. Sure, there are factors like the increasing number of independent and liberal Senators who could pose problems, which clearly weigh against major changes. There are some indications that the Harper government's changes spurred a backlash which contributed to the beating the Conservatives took in 2015. Suggesting they will have no more than a weak appetite for wrestling with citizenship requirements in the near future. But a lot can change between now and 2020, when any such legislation would be proposed.
My GUESS, emphasizing it is just a GUESS, is that there is NO reason to apprehend the 3/5 rule will change anytime soon even if the Conservatives form a majority government following the 2019 election. But other aspects of the requirements could be tweaked.