I mean, it's pretty obvious why soccer/futbol is the #1 sport in the world. There is a massive cost of entry for many other sports. Most families in canada can't afford hockey these days.
There's money in soccer, so I expect it to become unaffordable in NA in a decade too.
On topic: yes, it would work, but it wouldn't be nearly as powerful as in European football leagues.
The concept of loans is feasible because of several conditions:
1) The pool of players, leagues and clubs is vast;
2) Club-affiliated football schools provide a constant influx of young talent;
3) Advanced transfer market with colossal fees for top players;
4) There're no standartized contract limitations (it's possible to sign a 16-yo player for a 7-year , $40M contract).
5) Reserve players can go months or even years without playing, if their direct competition is obviously better.
These conditions eventuate in rich clubs (or clubs with strong academies) preferring to sign players very early to avoid the transfer fees race (or sell them for an astronomical price later) and loan the players who are in their long-term plans to teams who are not their direct competition. Team B then gets a player who can help them with their immediate needs, while Team A gets a player who is more experienced and in a better game shape at the end of the year.
The NHL exists in a relatively isolated universe with a strict system that supports losing teams and limits the power of wealthy clubs or clubs from the hockey-intense areas. So, while there are examples of NHL clubs making deals that don't have the advance of team's results as a primary result (like Horton trade to the Leafs by CBJ), the area with a loan as the best possible option would be very shallow: a stacked team could loan their NHL-ready prospects to below average teams that suffer from mass injuries, but that's about it.
For example, I could
potentially see the Caps loaning Miroshnichenko to the Blackhawks for a season (as,
simplifying a bit, Washington doesn't have an open roster spot for a scoring winger, Miro is too good for the AHL and the Hawks fans complain about their weak roster all the time), but it would raise other questions: improving their roster would interfere with Chicago tanking, a good NHL season would make Miroshnichenko less cost-controlled, an injury playing for another team would be very unwelcome, and so on.
Or if a team has a star goalie that goes down for nearly all season and very weak backup, so them even making the playoffs is in danger, could use the option to loan a goalie prospect from another conference.
So, while this system could possibly work, overall the NHL just doesn't have the room for it to be very important. And a loan-style deal could be made with basic NHL trade instruments anyway.