Most of that article is premised on a past that's no longer relevant. Tennessee HS football was mediocre for ages and only started to produce athletes in enough numbers to be a focus ~2015. Short of us seeing a migration out of the state, Tennessee HS football has reached where its floor should've been decades ago but nonetheless it's finally there and that shouldn't change in the coming years except to perhaps increase.
That said, it's hard to get bent out of shape about TN HS football when we've never been dependent on it. TN HS football is best looked at as bonus talent. We simply have never relied on in-state talent the way other programs have because it never existed in great enough numbers. Now that it does it's a bonus but it isn't what makes the machine run.