Not sure why I hadn't noticed it before but, when installing games I've played before on my PS4, the dlc I own for that game auto installs. Not sure if it's handled by Playstation or by the game dev but, seeing as TSW5 is on its way shortly, and the annual "download all the dlc after getting the brand new version of TSW" is about to happen, any chance you could put some code in it or have a chat with Playstation and get the updates to auto install and save me having to go through the faff of manually installing or even make it easier by not having to re download all the dlc I own (game + dlc now totals close to 214 GB).
Even better, bring the files across from the existing TSW4 installation (this goes for PC too) and only download any updates that actually need doing.