This is yet another case where I think the use of "temporal" is quite confusing:

MariaDB [test]> CREATE OR REPLACE TABLE t1 (s TIMESTAMP(6) GENERATED ALWAYS AS ROW START, e TIMESTAMP(6) GENERATED ALWAYS AS ROW END, PERIOD FOR SYSTEM_TIME (s,e)) WITH SYSTEM VERSIONING;

ERROR 4128 (HY000): Table `t1` must have at least one temporal column

Unless the wording is regulated by the standard, I'd suggest to change it. I think for an average user, if anything is "temporal" here, it's columns `s` and `e`, as they directly related to time, both by type and purpose. The next thought is that on some reason we require the table to have a column of a "temporal data type" (expression that is already used here and there); and only after all that one can start guessing that something else is meant.