The problem is that in cricket they are largely judging 3 or 4 objective issues. Where did it pitch, where did it hit, would it have hit. Or was he in or out and you can go through and tick the box as you go through
In RL there are a lot more subjective issues with regards to knock ons and obstruction. even Onside/offside becomes something of a subjective decision with the lack of cameras everywhere. It becomes impossible for the players to really be responsible for the referee.
In fact the current system proves how unsuitable this system would be for RL. The referee themselves refer the decision the VR because they aren't sure. If the referee isn't sure, it seems wrong to punish the players (by removing the 'challenge') if they turn out to be right.
I think too much is made of the VR, not just by fans but by the game. The set up for the VR is quite big and can add excitement in some situations but in others can detract from it. There is also the obvious intention to get the decision right.
I think the problem is that we treat the VR as a thing rather than what they actually are, another assistant. The ref could easily just consult the VR as they do a touch judge, and come to a collegiate decision.
Just use the VR like another touch judge and it should move the ones which the on field officials are pretty sure about a bit faster. If the VR has seen something he can ask for another look, if he is confident the ref will be a bit more confident to award the try on their own.
If the ref has seen something he should refer it to the VR, explaining what they have seen and come to a decision together.