IMO you guys are looking at the RS thing from the wrong angle.
You're seeking to find reasons why redshirting is bad rather than to ask yourself how often a true freshman makes a meaningful, year-long contribution. Having a true freshman start is incredibly rare. The angle you need to take is why is it worth their while to spend that year rather than have that time to transform their body, wrap their brains around the football concepts they're being asked to learn.
Jackson is a great example. He likely projected best as a safety, we plugged him in at CB hoping he could push for a #1 job right away and be the next Ralph Brown. He struggled, regressed, and played less as the year wore on. Now there is a battle at Safety and where he could be a very talented RS-Fr with a year of work at safety battling for that job, he's a Soph trying to get his mind right playing (arguably) his 2nd-best position.
Tre Bryant played some, but you'd be hard pressed to make the case that he was a make-or-break player last year. You look at how he ran in the spring, how he's figuring to be the #1 guy, what would it be like to get 3-4 years of him as a starter vs 2-3 years?
Yah but look at your base assumption. You are basically assuming that to have any value, a frosh would have to *start* if he's skipping a redshirt. Which I agree is incredibly rare. But that assumption is incredibly invalid, IMO.
But that's what the "I want it now" guys are looking at in terms of expectations of these kids because the cupboard has been so bare here for such a long period of time.
In a "normal" program with really good talent, you probably play most of your capable freshman in spot duties or on special teams (every group needs athletes right?) and the truly special ones become starters immediately.
Bama doesn't put 12 freshman in their starting 22 every year. And they get all the really good freshman.