“the large majority of frum Yidden are Yirei Shamayim”
Yes. But that does not mean at perhaps the most emotionally stressful time of their lives when they feel that their own well-being and and that of their children is at risk, frum yidden will act rationally and strictly in accordance with the technical requirements of halacha. I’m not sure anyone is suggesting that “the majority” of frum divorces, end up in contentious/bitter secular court proceedings. However, in cases of wholly-inequitable proposals based on the financial history of that relationship (not that infrequent as more women work outside the home as the primary or supplemental income earner) or where there has been any history of verbal/phsyical abuse, don’t expect otherwise “yirai shamayim” to act rationally. Sadly, the frequency of contested outcomes is higher than you seem willing to accept. Further, the statistics from EY you cite to may not be comparable to those in the US and UK where there is much easier access to secular courts to redress perceived inequities).