I don’t think they want to have access - they are given access voluntarily by users of their service. The mechanisms behind this haven’t been explored – maybe this has overlap with your SSS research (which I don’t know much about).
However, I think visibility is not the point here.
Even in the transparent domain, how do you find out that you own a resource (meaning that nobody else can spend it except you)? You must somehow be able to see that it has this property.
Should indexers maintain an ever-growing list of all resource kinds having the property of being ownable? How can you make sure that this list is up-to-date? To me, this doesn’t seem to work.
In an ideal world, we would be able to formally verify certain behavioral properties and invariants of resources and logics (such as “nobody else except me can spend it”) which @cwgoes has pointed out
but to quote him once more:
HOWEVER, for now, this is a research problem, and we should do something pragmatic for the devnets.
Standardized lookup would be a pragmatic approach, but it would require these fields to be maps.
I also think that there are other software components besides indexers wanting to inspect standardized application-related data that we haven’t encountered/thought about yet.