Indeed and there's many methods for this that are being used to restore many old films from archive. Modern film cameras used by major networks record at 4K-6K (full open). Beyond that even if the cameras on set are recording at 3.2K or 2K pro-res etc... it doesn't mean that the post-production and up-scaling upon rendering doesn't benefit from a final output of 4K. Finally - we must think to the future and not hold back technology to the lowest common denominator.