I don’t want to set a time limit on admin privileges.
I know of another company that has a feature built into their core app to allow their users to “switch” into other accounts. Sure this is mainly designed for people in that specific job that handles high privacy data (think PII/information of people under the age of 13) who log into their lower privileged accounts to do regular staff work and switch to their admin account with PII access when they need the access granted by an administrator account (their admins override ACLs much like the ones in Discourse).
The point I’m trying to make is: Some people (like me) may want a way that lets people start off in a normal/moderator account for day to day use (e.g. browsing the forum and posting) but give them the ability to log into an admin account with more access that doesn’t see day to day use (think toggling site settings, modifying the admin API and granting and revoking moderator status) or seems potentially dangerous in the hands of an attacker. By allowing for this switch people see only what they need to see and only assume the access they need for what they are doing at the time.