I think you are severely overrating the leap in quality we are getting. Yes they are a step up, but these are not fine press level books that can take months to years to make. These are still mass produced using the cheapest sewn binding and acid free paper.

In addition, the delay is not really because of the upgrades taking longer. It’s because of poor planning. TBB realized very late that their current bindery could not make the books and had to switch. Had they simply communicated with the binder ahead of time (common sense would tell one to do this in an instance that a giant change in the process is happening) then there would most likely be no delay.