https://www.internetlegalattorney.com/are-there-gdpr-exempti...
It's not a blanket immunity, but it's not universal as you say.
Yes, it's probably a drafting defect, but I think one would be very brave indeed to try to rely on it, especially given that establishing an art 30 record is, practically speaking, a prerequisite for being in a position to comply with the rest of GDPR.
Unfortunately, this is a good demonstration of two criticisms made of the GDPR right from the start: the costs of creating new paperwork in the approved format even if it makes no material difference to any actual data processing, and ambiguity about what is required or permitted even in quite fundamental respects.