My thought process watching it live was "wow, that's a brutal tackle". However, having watched the slow-motion footage multiple times during the VAR check I didn't think it was a red card, because I didn't think there was enough contact. Then I went back and watched the live footage where you could see him make the run and lunge in towards the player and I went back to thinking it was a red card due to him only going in there to make a mark on the player, which is completely pointless and potentially dangerous, and obviously stemming from frustration over how the game panned out.
This is one of those incidents where the amount of contact isn't the point, so I'll ask you to watch the live footage, watch the run he makes before making the tackle and tell me that he doesn't come in way too aggressively and only to take the player out? For me, that fulfills the criteria "attempts to use excessive force" and "not attempting to play the ball", which makes it a red card IMO.
Also, taking the slow-mo footage and making a point about the contact itself takes away the context that the ref saw, which is Wales 3-0 down, player making a lung-busting run in order to lunge in and tackle an opponent to the ground from behind with a tackle that had no chance to win the ball.