Barra, 1jz, 2jz, 4g63, rb30 etc have all had development in bottom end rigidity and been shown that their failure point can be raised to a higher power figure.
And have all managed to make well over 1000hp.
Sometimes double that.
If you look at how modern engines fasten their main caps six ways to sunday, and how often these motors can be boosted to the moon and make serious numbers reliably...it becomes clear that the rigidity matters.
I do understand that vibration and harmonics is part of the equation, but a well designed girdle should be able to dampen harmonics rather than amplify them. That requires a size/shape and density that resonates at a different frequency to the thing it's bolted to.
The idea that "they don't/can't work. not here, not ever. they're just a waste of money" isn't something I can get behind.
I'm quite happy for us to just agree to disagree on this one.