As ArabCheif says, in theory, almost every tackle is dangerous, and those at speed - ball carrier or tackler - even more so.
So it seems that this tackle wasn't simply dangerous, it was excessively dangerous/reckless. Where is the line from "acceptably" to "reckless"? Good question, and difficult to draw.
As I said in an earlier post, my real issue is how it has been treated. 24 weeks starting point is just laughable. It seems to me that the Disciplinary system is broken.
Are we meant to use intent? Jordie Barrett would suggest not, nor the other South African citing for charging into the ruck.
Are we to use dangerousness? Well, there's a mixed bag of thoughts there. This case suggests yes; the two other cases suggest not. The Quins winger case suggests so.
Is it outcome based or input based? No settled views here.
There's a trend starting to emerge of inconsistencies in how these things are treated, and I'm not sure for the better. SANZAAR in particular are leading the way in, I think, increasing risk to players.