Every newly created account should also be autocreated on loginwiki, but for some reason that's not happening anymore.
No idea what causes the problem, are these accounts probably created via API? Is it related to T74791 or is this a separate issue?
See for example:
Wondering if there is a relation to T124468 though we reverted to 1.27-wmf.10 in the meantime already...
Accounts normally get auto-created on loginwiki because of the redirect dance CentralAuth does to get the cookies set. When the redirects don't happen, e.g. because of accounts being created via the API or bugs like T124468, the auto-creation doesn't happen.
Duplicate of T125133: Accounts are not autocreated on loginwiki.
There is a job (CentralAuthCreateLocalAccountJob) to make sure autocreation always happens on loginwiki. It got broken because of the permission change.