This sounds like what regular commit messages do. How are conventional commits specifically helpful?
replyConventional commits (especially with git emojis) show at a glance the blast radius of the change (eg whether it breaks the product itself or just some internal dev tools). Emojis help immensely when looking at dozens of commits at a time.
replyThat information should still be in the commit messages. "No functional change intended." appears widely in FreeBSD commit logs when code is being refactored (or, rarely, restyled).
replyAnd the issue isn't whether you can remember what you changed yesterday; this is largely about making sure other developers can quickly identify relevant commits. If you're a solo non-OSS developer, this is entirely relevant to you.