Application
6 This Act applies in respect of a digital news intermediary if, having regard to the following factors, there is a significant bargaining power imbalance between its operator and news businesses:
(a) the size of the intermediary or the operator;
(b) whether the market for the intermediary gives the operator a strategic advantage over news businesses; and
(c) whether the intermediary occupies a prominent market position.
So it would be up to the CRTC to decide whether or not to put HN on the list of "digital news intermediaries" by applying the above 3-part test. Given that HN is a (relatively) small forum, compared to Google or Facebook, it's unlikely for that to happen.
Basically it only applies against you if you're big/important enough. I assume in practice this means Google, Facebook, Twitter, Bing, Apple, and probably some others. Reddit, I suppose.
Remember that even though people misleadingly call Google and Facebook tech companies, they are in fact advertising companies; and although people speak of news companies, they have generally seen news, opinion and analysis as tools for connecting eyeballs to advertising i.e. they're effectively advertising companies. This bill is about the direct competition between the two kinds of advertising companies - traditional, ~domestic companies with close and personal ties to the people who govern vs new, foreign companies who don't have such essential ties to politicians as journalists do.
If it were literally just about the provision of news, then Canada and Australia fund the CBC/RC and the ABC/SBS so why would they be so fussed? There are people who today make a living from podcasts and substacks who could not make money from traditional advertising/media companies. News would be provided.
(In fact, just to bring the point home, the original version of Australia's equivalent bill didn't allow the ABC and SBS to participate, because as government-funded media organisations they didn't suffer from the transition of advertising from news-sponsoring to tech-sponsoring in the same way as private companies.)