The ruck is probably an area WR (World Rugby) needs to actually address if they're going to keep rolling out player welfare lines.
Trying to 'pilfer' the ball has become all too common of 'sealing' off the tackled player and the defender makes no real attempt to win the ball. Additionally, defenders now fully cover the ball, duck their necks resulting in their head being the lowest and furthest part of their body.
I'd say WR (World Rugby) needs to issue guidelines that a defender needs to keep their head up and leave a gap between the tackled player and themselves. This then gives the attacking team something to aim at when they do a clean out.
In this particular instance, I'd argue Brown was so far forward that he wasn't even maintaining his body weight.
Right knee is resting on the tackled player and both hands are on the ground supporting his weight.
With the placement being so far away from the defender, Brown should have stepped over the tackled player, but he went to go as low as he could and paint a picture of stealing the ball.