Move the new logic to the `externalAuthenticationSystemUsed` function

services/web/app/coffee/infrastructure/Features.coffee

@@ -2,7 +2,7 @@ Settings = require 'settings-sharelatex'
 
 module.exports = Features =
 	externalAuthenticationSystemUsed: ->
-		Settings.ldap? or Settings.saml? or Settings.overleaf?.oauth?
+		Settings.ldap? or Settings.saml? or (Settings.overleaf?.oauth? && !Settings.createV1AccountOnLogin)
 
 	hasFeature: (feature) ->
 		switch feature

services/web/app/views/user/settings.pug

@@ -148,7 +148,7 @@ block content
 
 							hr
 
-							if !externalAuthenticationSystemUsed() || (settings.createV1AccountOnLogin && settings.overleaf)
+							if !externalAuthenticationSystemUsed()
 
 								p.small
 									| #{translate("newsletter_info_and_unsubscribe")}