Very true, and I would probably agree with your position if it wasn’t for the fact that BOD was taught exclusively and explicitly for the past several centuries by basically everyone in the Church.
And, at the same time, the requirement for explicit faith in Christ and the Holy Trinity was taught exclusively and explicitly for 1500 years before a Franciscan and Jesuit decided to float Rewarder God theory, and now the same Trad bishops/priests who are most hostile to "Feeneyism" almost universally reject it. It was also upheld by the Holy Office after the invention of Rewarder God theory. Similarly, it was exclusively and explicitly taught for about 700 years, following St. Augustine, that infants who die unbaptized suffer (albeit mildly) in Hell, until Abelard first questioned it, St. Thomas also approved it, and the Church ended up endorsing the notion of Limbo. Vatican II was accepted by all theologians as well. Msgr. Fenton explicitly rejects what i have termed "Cekadism," some mythical "infallibility of theological consensus" that he invented at some point.
Nor has anyone demonstrated that BoD is anything more than theological speculation. There are two ways to demonstrate that something has been revealed (apart from explicit revelation in Sacred Scripture):
1) Unanimous consensus of the Church Fathers. But 5-6 Fathers rejected BoD outright, 1 (St. Augustine) tentatively floated it as speculation but then retracted it, and 1 (St. Ambrose) IMO did not hold BoD in the sense that it can save, holding that such a one would be "washed but not crowned." So the majority of Fathers rejected BoD.
2) Theological (syllogistic) demonstration that it flows logically and necessarily from Revealed premises. This has never been done. Mostly there are appeals to "Augustine and Ambrose", St. Robert holds that it "would seem too harsh", and the vast majority of theologians just say, "Yep. BoD." St. Thomas made the only attempt I know of, but it amounted to more of an explanation of how it might work rather than a proof that it exists. He explained that Sacraments have a visible and an invisible aspect to them, and that BoD invisibly provides the benefits of Baptism. Just because some graces of the Sacraments CAN be provided outside the Sacrament, it's also true that others cannot. In fact, the ones that cannot are the ones that tend to confer a Sacramental character (Holy Orders, Confirmation). But so does Baptism. So the closest thing to actual theological reasoning I've ever seen falls short of actually proving BoD.
Consequently, I hold that BoD not only has never been defined, but that it's not even definable. Simply because something has become the prevailing opinion on a subject (cf. St. Augustine's opinion about infants who die without Baptism) doesn't make it infallibly true and irreformable. If it does, then how comes many of these SV bishops/priest who hold this reject the requirement for explicit faith in Christ and the Holy Trinity, which was taught explicitly and exclusively for 1500 years, and is in fact enshrined in the Athanasian Creed? They hold the opinion of some Jesuit innovators after 1500 years of unchallenged and unquestioned teaching. So two or three hundred years of theological opinion (questioned by another Jesuit, Father Feeney) pale in comparison. Yet they do not wish to see their contradiction on the matter. These same SV bishops/priests also reject those who hold St. Thomas' opinion on the need for explicit faith as also being heretics. I bet that if I told some of them that infidels (Jєωs, Muslims, etc.) cannot be saved, I'd be denounced as a "Feeneyite" heretic ... rather than a Thomist and a First-1500-Years-of-Church-Teaching-ist ... and refused the Sacraments. When I was at STAS, there was a priest there teaching the requirement for explicit faith in Christ and the Holy Trinity, and Bishop Williamson admonished him for being "close to Feeneyism".