Increased RAM consumption in GROUP BY b/w MCS 5 and 23.0.2

A query on joined Columnstore tables using COUNT/GROUP BY and HAVING yields error about memory limit

It aborts with the error: "Error Code: 1815. Internal error: MCS-2003: Aggregation/Distinct memory limit is exceeded", after about 80 seconds.
For the attached data this is happening on MariaDB 10.6.12-7-ee CS 23.02.3, but not on 10.5.19-14-ee CS CS 5.6.8, where it finishes correctly returning 66 rows in about 2 minutes.