The catylist for that change was Mike Keenan and the mid-1980s Philadelphia Flyers.
At the start of the 1980s, players constantly took 1-2 minutes shifts. When you watch old games, it sticks out like a sore thumb how long the shifts are. One in particular I remember is Gilbert Perreault scoring after being out forever during the 1972 Summit series, then staying out for the faceoff after the goal.
Keenan realized that fresh players being constantly cycled over every 30 seconds would dominate tired players who'd been out for over a minute, and it's one of the biggest reasons those Flyer teams dominated despite having pretty average personnel.
By 1990, everyone had caught on, and short shifts were the norm.