No, the point of Zotero Storage is to make all your files available on all devices, whether or not you have them locally.
In an upcoming version, it will be possible to configure a given Zotero installation to remove local copies of downloaded files if they haven't been opened in a certain number of days in order to free up local disk space.
Upgrade Storage
In an upcoming version, it will be possible to configure a given Zotero installation to remove local copies of downloaded files if they haven't been opened in a certain number of days in order to free up local disk space.