The NY Yankees have traditionally had captains but usually bestow it to exceptional players who have exemplary character and work ethic. I think it’s largely ceremonial and is more intended to honor the player than actually appoint him as an erstwhile leader of a team.
Examples of New York Yankees past captains are Derek Jeter, Don Mattingly, Thurman Munson and Lou Gehrig. All of these players became captains after long and successful careers as NYY players. Although the Yankees captaincy is currently vacant there are several future candidates on the team, the two strongest of which are Aaron Judge and Sir DIDi Gregorious. If Gregorious is made captain he would be the first captain who is also a Knight and there would be confusion on whether to call him “Sir DIDi” or “Captain Didi”.
On the current Habs team the only player who is remotely by this criteria Captain material is Gallagher. However Gallagher isn’t as good a hockey player as the Yankees captains I mentioned above were as baseball players. You have to be really good and put in years of quality service to the team. Markov could have been made a Captain his last few years on the team, IMHO, but the Habs organization didn’t want a Russian in their captaincy. It’s not really fair to Markov because he deserved it after all of his years of service. If he was French and from Quebec, his captaincy would have been more automatic than my hard on the last time I saw Dahlia Of Euphoria. It is what it is. He will be captain of his KHL team probably.