And (likely) tooling for altering/fixing samples, and (likely) updating their transcoding process to include thumbnail generation at all the various sizes and qualities they encode for, and backfilling all the existing titles to fit into all such tooling, and coordinating such a project across what are likely multiple teams with different roadmaps and reporting structures, and doing it all without service interruption (lockstep deployments of all the various moving parts).
So much slow in large organizations. So much.