Speculating here....IF (and an big if) the Bengals were even taking phone calls to possibly trade that pick, how much draft capital was everyone comfortable with?
I think the price would have been higher than all of a team's draft picks that particular year, and might have been multiple high draft picks in ensuing years.
Is the value of a franchise QB so much that a club hamstrings itself to build a team around said franchise QB? We saw for years what an average or below average defense with a QB playing at a HOF level...yes, multiple average seasons around .500.
Regardless of who is playing under center, an NFL team has to have talent and good play at other positions for the team to consistently win. A HOF QB can mask a lot of weaknesses, but only to a certain extent.
Frankly, I don't think they were even entertaining any offers, and it's likely they made the price so high that no team was willing to even consider it.