This was recently added to emacs-29 as

  commit 5258f3616812da63526da7b1aadfe26fc384ef2a
  Author: F. Jason Park <jp@neverwas.me>
  Date:   Sun Nov 13 01:52:48 2022 -0800
  
      Accept functions in place of passwords in ERC
      
But I forgot to increment the logging-format version number. Here's a
patch that does that and also ignores incoming messages when checking
for redacted secrets, which is currently pointless. Anyone interested
please take a look (preferably in the next few days). Thanks.