Thanks for replying Dominik.
Indeed, by some reason, PVE thinks that all my storage is clean, and all my content is inside CTs and VMs, but, at least in my case, is quite the opposite: all my really valuable and relevant content is in the host storage itself, and all my CTs and VMs are really disposable, because they serve only to manage/show/display/use my data storage.
Thanks for the link to suggest the feature.