I have some relatively strong anecdotal evidence coming from a low-fat diet to a (somewhat) low carb diet, and from 4x/week strength training with lots of faster reps to 2x/week of exercise with very few slow reps, that the 4HB guidelines are on to something.

The biggest thing I discovered after listening to the patronizingly 4-hour-abridged 4HB audiobook is that there's very little relationship between (willpower, time investment) and benefit.