“To prevent battery depletion and to protect the components, install the derailleur battery blocks and battery contact covers before transportation.”
Just follow the manufacturer’s advice, IMO.
Or potentially void your warranty, up to you. There doesn’t need to be all this why?
The advice is there for a reason, and the manufacturer has given this advice, no need to ask strangers on the internet, battery depletion is not the only reason (probably, it’s not the reason we give the same advice with the devices we make.)
If you find the guidance not to your liking or inconvenient direct message them and ask for the reasons for their advice and make an informed decision.