Presumably physical collectible assets (maybe also virtual ones too for the NFT crowd) will be assessed differently from more liquid assets for the basis of evaluating a wealth tax, especially in the event of surging valuations from the collectibles market. If real life taxes, like say property tax in California, can be reined in by measures like Proposition 13, then there's no reason why a real-life wealth tax won't be subject to all sorts of internal controls and effects from lobbying. Thus protecting the "run of the mill average Joe" from having to suddenly sell his mythical rock.