Digital licenses are assets. Intellectual Property. I would argue that intellectual property is legally part of an estate. I have invested years, sometimes decades in developing my gaming worlds and buying digital assets to populate those worlds. Time and money. Those investments are transferable, regardless of any 'terms' imposed on license holders and similar attempts to circumvent laws.
I have added all my login info and keys to my vast collection of games to my final documents. My beneficiary will be able to benefit from the years I have invested in those licenses.