You cannot change this behaviour. As suggested if you have a need to you can CAST the time as suggested.
In previous versions we effectively did this within the AQ$QUEUE_TABLE view but that and the DST issues led to a re-think. This means that AQ is not affected
by DST changes anymore but does mean you may need to cast the values.
Yes you correct casting is all what we are going to do. On the other hand, why DST is unique to enq_time? sysdate is working fine. Now we have to write cumbersome from_tz function which is a pain in the neck.