Really talking about Chatham Asset Management and PostMedia (a subsidiary), that own almost 80-90% of print media (written news and periodicals, including almost all rural papers and online content). Even now, most people I speak to barely know about either, and it's reach is way beyond the listed periodicals.
Is this as big a deal as it sounds? Kind of. Because the CEO determined they were "insufficiently conservative", he appointed Kevin Libin to coordinate all of the organizations under their umbrella to provide "reliably conservative media." Consider what that phrase even means - it's not perspective, it's an introduction of bias. This isn't something that really exists anywhere else in Canadian News ecosystem, even in the far right, and is one part of the media ecosystem's challenges.
However, they also get the benefit of being "center" between lunatics like Rebel News and True North and the CBC; this gives both them and further right rags more legitimacy than earned by virtue of the total absence of a Canadian far left media ecosystem, hence the attacks on the CBC itself (which does contain editorial, but is general one of the most fact based and investigative journalism driven media organizations in Canada). It also allows them to "create a consensus" by essentially just agreeing with themselves.
Even the Toronto Star, one of the "most left" credible independent media organizations, is now under (separate) conservative ownership.
Frankly, if you're a subsidiary, you should be forced to wear every one of your ownership's emblem "Chatham/PostMedia presents" in double font every time you throw up your Vancouver Sun or Calgary Herald.
You don't have to like or dislike any of these organizations, but the total lack of transparency while structuring this discussion as central consensus is about as disingenuous as you can get.
Things like Ground News (factuality and partisan bias news screeners) help somewhat, but require some literacy in terms of statistics and data. It's worth learning tools like these (or tracking it yourself across everything you read, and looking at a wide berth of the various perspectives in Canada, which is extremely laborious especially in an age where we can barely get people to click past headlines, hence the specific name drop for Ground News which does a lot of this for people).
The main takeaway: The centralized role of coordinating a wide breadth of media organizations and incrementally corralling them towards one narrative, something essentially unique in the space no one else has, and with total lack of transparency, is the biggest distinction between them and everyone else.