I saw one team in my life that I felt was truly hitting people harder than anybody else, and that was the '85 Bears. Gary Fencik, Mike Singletary, Steve McMichael, Otis Wilson, all of those guys seemed to fly around and hit a little harder than everybody else.
But in all likelyhood, those are just hyperbolic memories of a 9 year old, enhanced and exaggerated by years of hearing how legendary that team was.
You can't measure physicality, and you can't convince me that Team A is "more physical" than Team B. That's just stuff that talking heads use for talking points. "The Ravens want to play a physical ball game, and beat you 6-3". No they don't. If the Ravens could score 40, and beat you 40-3, they would. It's silly. What team doesnt want to play a physical game? "Alright guys, let's avoid contact today!".