I’m not underrating it, trust me.
Chara’s physicality wasn’t more than what Pronger brought. His strength and sheer size was the advantage over Pronger. That wingspan was ridiculous, unique in the history of the sport. And he wasn’t just a big hitter, he was physically stronger than any of his opponents and knew how to use it. His dad was an Olympic wrestler, and Chara trained at Greco-Roman in the summer. Trying to battle him along the boards wasn’t about Pronger-style nastiness and physicality, it was about a giant man using leverage that would just smother an opponent the way an ordinary man could restrain a child.
The biggest flaw with Chara was that he didn’t have the skill level to really dominate the puck. He could pound it as long as someone set him up, and he was usually able to get a stick on anything within 15 feet of him. But he wasn’t a particularly effective rusher or point QB… not that he was bad, but you wanted someone else on the ice who could do a bit of playmaking for him. That’s where he gets eclipsed a bit by the peaks of guys like Lidstrom and Keith who put it all together in one package even if they lacked the physical dimensions of a Chara. And certainly you’d look at the impact of a peak Ovechkin, the physicality he brought along with the offensive domination, or peak Crosby or Malkin, and Chara didn’t quite have that level of game-takeover skill. If I had to rank him against forwards I’d say Chara was more at the Datsyuk level of impact, and Datsyuk notably didn’t hold a candle to those big 3 forwards either.