Rules generator has gone crazy!
A lot of people have notified me that too many rules are being generated now. This is a known regression bug that stems from a fix put in v12.1.0 to address the “No fields have been changed” error many people complained about. In implementing this fix, I made the algorithm too relaxed, so now it picks up a lot of fields that were magically hidden by Lightning Autofill before. This has been fixed in the next release, which will drop soon.
Sorry for the inconvenience, but you should take this opportunity to see just how crazy complex some forms can be — tons of hidden fields!