Since they’re robots, automated tests and manual tests are effectively the same thing.

I'd buttress this statement with a nuance. Automated tests typically run in their entirety, usually by a well-known command like cargo test or at least by the CI tools. Manual tests are often skipped because the test seems to be far away from the code being changed.

My all-time favorite team had a rule that your code didn't exist if it didn't have automated tests to "defend" it. If it didn't, it was OK, or at least not surprising, for someone else to break or refactor it out of existence (not maliciously, of course).