It probably is more like the LLM is able to „pack the truck much more efficiently“ and decompression should be the same.
But I agree that the likely use-case of uploading all your files to the cloud, having it compress your files, and downloading the result which is a few kb smaller isn’t really practical time efficient or even needed at all.
Maybe it’s a kind of dummy content for the test phase? Pretty sure too many people blocked ads and this is their solution