Problem is how the ruck is refereed. Interpretations favour certain playstyles and certain players.
I'd make it black and white with and idea to allow for struggling at first impact of the tackle, afterwhich a simple count and play the ball. No wrestle, no endless struggling with no progress. As soon as progress is reduce to a struggle the count begins.
Currently teams with either more size or better wrestling drills have a ruck advantage.
Smaller or less technically proficient sides spend more energy at the ruck contest, which reduces line speed, and increases meters of the opposition. The fatigue eventually hits hard and defensive gaps open up. Now do you reward wrestling skills? If i was the NRL i'd do the fan test, if wrestling is increasing entertainment then encourage it, if it is detracting from the spectacle then remove it. For size there is only a limited pool of big skillful hard working players - once that pool is exhausted then there are tradeoffs (skillful little guys like Fulton, big guys with skills but no work ethic - Pritchard, big guys with no skills etc etc) .
A similar reason causes blow outs in AFL - the weaker teams such as GWS have inferior/inexperience/younger rosters and so their players have to expend more energy to do the same thing as another team who uses less. Every ball they win, every clearance - is less efficient and saps more energy. Now that is natural as the game is not structured at all. With league the ruck is a highly structured part of the game open to interpretations. Making solutions to fix the ruck much more practical and impactful…
The solution i put above theoretically should encourage the game to be played with ball movement and with physicality in the initial contact and immediately subsequent to that contact. With a standard count then players would no longer need to flop three blokes in each tackle to give time for their teammates to retreat.