I have a different view on this.
While the Law makes Jackson partially right with his yellow card and World Rugby's decision to ban Finn Russell means it should have been a red card, I have a thorough dislike for the way in which World Rugby is managing this specific focus on protecting the man in the air. IMO, it does not fit into what I consider to be the traditional fabric and spirit of the game. A player should not be penalised, let alone yellow or red carded, for essentially doing nothing other than standing still to catch the ball. As far as I am concerned, any player who recklessly jumps into the air without any regard to where or how he is going to land, and who then expects everyone else to just get out of the way, deserves whatever happens to him. Why should a player, say a fullback, who is absolutely stationary, with his feet firmly planted, eyes on the ball, be expected to get out of the way because some idiot is sprinting at him and jumps at him from 20 feet away? By all means, if the defender intentionally tackles, or strikes , interferes with or moves into the path of the jumper, then fair enough... red card. But if the defender is at the point where the ball will alight, not moving and waiting for the ball, then gets clattered by the jumper, its the jumper who should be penalised.
Personally, I would like to see the introduction of either a Law change or a protocol to deal with this. Either don't allow any players in the kicking team to jump for the ball, or bring in something similar to basketball's "charging" rule. In basketball, if a running player runs into a stationary player, the running player has committed a "charging foul". If the defender is moving when the runner runs into him, then the defender is "blocking".
There definitely needs to be a change. Sooner or later we are going to see two opposing players running in opposite directions, jump the way Biggar did resulting a horrendous collision where one or both are going to end up seriously injured.