trong>Security:</strong> SPIRE registration entries are the root of trust; removing them
is the most secure and auditable way to block access. Infrastructure controls
are also robust and well-understood.</li>
<li><strong>Operational Clarity:</strong> The lock/unlock state is unambiguous and enforced
at the trust boundary or infrastructure, not in application logic.</li>
<li><strong>HA/Scaling:</strong> No need for all Nexus instances to coordinate or poll a
shared lock state, avoiding performance and reliab