The question of how we get guys to go is an interesting topic. Back when the Olympics were a thing that NHLers attended (remember those halcyon days?) Hockey Canada had been telling guys that previous experience with Hockey Canada would tip the balance for bubble players, so you would think that with Cortina coming up, that might spur the interest of players who would make a real difference at the worlds, and who might otherwise be on the outside looking in for Olympics.
But I'll bring my union organizer experience to bear here and say Hockey Canada needs to do the work, and not just in March and April leading up to the tournament. For one, they have players come through their events multiple times a year - the U17 tournament, the Hlinka/Gretzky tournament, the U20 and U18 tournaments - and they need to lay some groundwork down there. You can play the patriotism card, although that is the last bastion of scoundrels, or you can play the loyalty card (which is related to the patriotism card, but less scoundrelly). But you can also talk in practical terms of how these tournaments matter in relation to the Olympics, which the players do actually care about. A string of good results will give Canada a favourable draw in the Olympics, and a string of bad results will mean Canada has to get through Finland/Sweden/US earlier than we'd like.
And the thing about organizing people is that it has to happen frequently and early. Hockey Canada need to reach out to players early - like during NHL training camps - just to ask them to keep the national team program in their minds. Of course, in September everyone is a Stanley Cup contender, so no player wants to think about an early end to the season, but if you remind them about the reasons outlined in the previous paragraph, you might get guys more amenable if the ask comes in April.
And finally, the best organizing comes from friends/colleagues/peers. Hockey Canada should get guys who have gone to worlds, had good experiences, to reach out to teammates and friends on other teams to help recruit guys. Again, that work needs to start in September/October. Similarly, get some guys with lots of world championship experience - Shane Doan, Ryan Smyth, for example - to help spread the word.
Ultimately, you need to get Canadian players excited about playing for their country. They're super excited to go for the U20 tournament. They're super excited to go to the Olympics. They need to hear that while the worlds is in some ways a consolation prize, it is still important in the overall Hockey Canada program and is worth the effort for players to put in when they can.