What I think everyone missed is the referendum recommendation. Specifically,
Observation: The Committee acknowledges that, of those who wanted change, the overwhelming majority of testimony was in favour of proportional representation (PR). The Committee recognizes the utility of the Gallagher Index, a tool that has been developed to measure an electoral system’s relative disproportionality between votes received and seats allotted in a legislature, as a means of assessing the proportionality of different electoral system options.
The Committee recommends that:
The Government hold a referendum, in which the current system
is on the ballot;
That the referendum propose a proportional electoral system that
achieves a Gallagher Index score of 5 or less; and
That the Government complete the design of the alternate
electoral system that is proposed on the referendum ballot prior to
the start of the referendum campaign period
More than anything else, a referendum is what the Tory members of the ERRE committee were pushing for and they damn well got it. A referendum is a political bludgeon that tends to benefit populist sentiment more than considered opinion. Brexit, Indyref in Scotland, the last Quebec referendum, the rise of Trump, and some of the Harper era antics around proroguing all show how populist appeals can confuse complex issues in voters minds. The fact that the committee also included a relatively complex formula that would need some time and effort to explain as part of a referendum question is probably unhelpful.
Because as soon as it goes to referendum, the Tories can come out with all sorts of fear-mongering rhetoric probably linking PR to some kind of commie-hippie-ISIS-Liberal plot to corrupt your precious bodily fluids.
Because the last decade of Conservative governments show they can't quite nudge past 40% of the popular vote. The Conservatives are in an existential crisis as each new generation of voters are less and less conservative minded, and the older stable generations of Tory supporters are shuffling off this mortal coil. PR does not help Conservatives win elections so they will do what they can to sabotage it.
So what happens if electoral reform goes to a public vote and the Conservative fear campaign wins? ER is shelved. which is pretty much as good as never happening.
If the Liberals impose it sans referendum, they'll be accused of ignoring the will of Canadians and undermining parliament. If they don't they'll be accused of breaking a key election promise.
Viewed this way, the committee report is toxic to PR.