The systemd people are trying to fix something that's not broken. Binary logging is unnecessary and harmful. Windows uses binary logging for everything and is worse off for it. The beauty of plain-text logs is the ability to use normal tools and easily compose pipelines. When you switch to a binary log format, you either lose these benefits, or have to convert to text before manipulating logs anyway, in which case you lose all the purported benefits of binary logging.
If you want cryptographic signatures in your log file, you can include a signed hash field _in the text format_ without having to discard 30 years of refinement.