A wiser Medium contributor than I said once said that "politics is usually more complicated than it seems." So true. The reality is that campaign promises are easy to make, but hard to put into practice.
A good analogy is starting a small business. Many people who have never started a business think it is easy. But there are a lot of pieces need to be put together. Plans need to be made, for failing to plan usually means planning to fail. Then plans are adjusted because things just don't usually work according to plan. Starting a business is much easier to say than do.
I would like to offer my take on your points. However, I have already written an article on Mr. Trudeau's failure to reform our electoral system. I think breaking his promise was a good political call:
https://medium.com/tiered-democratic-governance/the-optics-aint-good-618f40817b2f