I have opened a discussion in the authorization panel space solid/authorization-panel#258 on the topic "Use WAC ontology for authorizing authentication". This issue here can then be used later to report on the consensus.
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One can use the WAC ontology to authorise Wallets to sign requests for particular resources.
That would reduce the need to have Access Control Resources specify lists of clients they want to allow access to, and also be bring together all the rules for user agents in one location.