ha, I thought I found an error in your analysis — but turns out you were right: Muscle mass increases and resulting strength potential often cant compensate for/catch up with the total body weight increase.
I tried simulating this by using Greg Nuckol´s calculators of his article you probably know: https://www.strongerbyscience.com/your-drug-free-muscle-and-strength-potential-part-2/
[Caution: In another arcticle https://www.strongerbyscience.com/which-weight-class-is-best-for-you/ , Greg uses allometric scaling to show that body mass increases while staying at the same BF % increases relative strength! Why? Because allometric scaling is not the same as strength/BW and is more “lenient” to mass increases. I believe its the better metric to compare strength accomplishments interindividually (such as in PL/WL competitions, the scenario Greg aimed at). But of course simple strength/BW is better for predicting sporting performance in some sports where your own body weight is the only resistance.]
A realistic example would be increasing muscle mass from a body weight of 70kg @ 12%BF to 77kg @12%BF which is an FFM increase by 5kg and a body mass increase by 7kg or 10%.
However, the corresponding increase of the max predicted “Total” (squat + bench + deadlift as one marker for max strength, with rather low current values filled in: 100kg/70kg/120kg) is from 573 to 613kg, only a 7% increase.
I´d like to add though, that if there is any external additional (heavy) resistance involved, for example moving/defending against opponents or objects, then max strength becomes more important and can override the slight worsening in relative strength.
So again, the decisions are highly context dependend which I think is the very point your are making in your excellent “strength is specific” articles.