I delete the vault cache after downloading then adding too or creating a project. Unless you need them to put into other projects down the line you won’t need them in vault cache saving you space.
It will cache what’s needed to you’re project after you have created or added it you don’t need to keep it in vault cache.
The cache is useful for other things so you may need to keep the file there if it’s something you’re adding too many versions & projects, will save you redownloading the file everytime you add something too a project, or if you need to quickly convert a particular version you might keep it in cache but when you have over 500GB in shaders alone in one project like mine you might want to just keep it per project and not cached because it will eat up space.