In an effort to protect team owners' investments (lmao), there will now be a penalty assessed for hitting the boards too hard with your body. Now, for clarity, all of the other penalties still exist, including those for unnecessary roughness or inappropriate usage (high sticking, slashing, checking from behind, etc). However, if either the subject of a hit or the hitter themselves hits the walls with sufficient force (as determined by a totally-not-costly pressure sensor put on each part of the boards), they're instead assessed a minor penalty.

Now you might say, "wait a minute, the game will just be a bunch of pansies who never get close to the walls or skate fast!" And you'd be wrong, because all of the hard hitters in the league would just try to body players straight into the wall instead. There'll be WAY more 4-on-4 time and lots of extra physicality rather than the opposite, because by hitting a player into the boards hard enough you can effectively kick them out of the game, giving enforcers a "safe", only mildly game-illegal way to enforce a penalty on a player. Aggression becomes a true and real attribute to increase and powerplay lines become some of the most important in the game.