There is, all-in-all, accurate information in this thread :)
IB's are exceedingly rare; pristine IB's essentially extinct. Fading on a pristine print is essentially negligible at this point. Scanning is a big deal. At 4k, scanning multiple passes also requires 30-40TB of storage. In Star Wars' case, absent the negative, absent complete color sep masters, a combination of scans from IB prints and low-fade Eastman prints would yield a fantastic restoration.
_Mike