You've conflated two different things.
I said Witten's production doesn't warrant paying him 8 million dollars per year.
Seperately I said that Witten will have a harder time getting into the HoF than many fans think and I've listed many reasons for it. First and foremost is the reality that tight ends in general have trouble getting into the HoF. Following that Witten has so much competition, and that he falls short in TDs... I wouldn't be surprised if he never makes it in.
You are correct IMHO to judge him at 8m if that's the cap hit. His cost to the team is just that, his cap hit, not his base.
Especially since his base changes the the minimum almost every year anyways.
But you'd be incorrect about in the Hall of Fame.
Yes, TE have had issues getting in.
That is because they didn't catch enough passes or have any statistical leverage to argue for their inclusion.
Witten has no issues there.
He is 3rd in active players for receptions. 17th overall. He'll hit 900 next week in all likelihood.
He is 7th in active receiving yards and 41st overall.
It is likely Witten passes Irvin for most receiving yards by a Cowboy.
Both numbers are climbing now rapidly.
Gonzales and Gates will get in as receiving options.
Witten will get in because he has elite receiving numbers and people know he can block too.
He's made a zillion pro bowls and been All Pro more than once.
He has an elite resume with a team who will champion him.