It's was definitely a red card. The Tackle was illegal.

Take a look at this analysis of the tackle on Grant and learn why the rules are very clear.

He’s been cited.

..

reckless play atleast.

In rugby, the term tackle refers to a type of action.

This guy did not go for a tackle (in which case his action could have been less controversially dismissed as a red card)

He went for an interception.

The defender needs to assess the danger of his actions.

Full body turn into a kicker... ref and tmo were gutless.