Egad. I remember that. Was a big Bruins fan back in the day, so...I remember this.
I stopped watching hockey back in the mid-late nineties...it became unwatchable for me with all the clutching and grabbing.
I thought hockey was a much better game when players did not have to wear helmets. It was certainly a more wide-open style of play and marquee players like Bobby Orr, Phil Esposito, Bobby Clarke, Guy LaFleur, were much more recognizable on the ice without helmets.
Injuries did occur due to no helmets but only a handful of very serious ones that I remember (and serious injuries still happen today). Also, not having helmets on the ice tend to increase one's situational awareness and vision on the ice (players from the helmetless era have corroborated this).