Very debatable IMO. Though the diving into players legs/knees is way too risky.
What is your opinion regarding the AFL's physicality in comparison?
The real difference for me is a couple things. One is that in Rugby, tackling is an art. Yes you have to be physical but there is so much technique along side governance to ensure that, on a general basis, it is less physical comparing on absolute terms. In the NFL players still use helmets and pads as a reason to think they can be brutal.
Secondly the way the NFL is with the gaps etc. to me means each play is like an intense burst. Which consequently makes impacts harder and more likely to cause damage for which recovery is needed. In rugby it’s a bit more fluid. I’m not a scientist so don’t know which takes a worse toll for your body.
Edit: Thirdly wanted to also add that the way impacts happen are different. In a scrum you’re not colliding in the same way as you do on the line in the NFL. Rarely do you have contact with big sprints face to face. It’s usually with a short run up in rugby.
But just to be clear that’s purely based on average typical games. It doesn’t mean that the peak damage is more or less in one or the other. Also doesn’t mean that one is necessarily safer than the other.
I think it’d be really interesting to compare injury statstics between Rugby and the NFL.