Some VST’s do have their own patch management, some better than others but it’s probably very hard to implement it within Cubase, for a start, categories are not universal, I would think the tagging also isn’t universal.
Maybe for VST4 or even 3.1, developers can implement tagging of individual patches from a set list, and each patch is an individual file, much like you see it on Sylenth, Massive, Diva etc, then it should be feasible to implement it with ease.
Right now, I just try to remember some of my fav patches, if I can rate them, I’ll do that, else for some VST’s like Spire (with a rubbish patch management) I simply save that individual preset to a particular folder.