Because this AD is a temporary fix for something that clearly wasn't foreseen by Airbus but it takes no time at all to press these buttons as they are next to one another. In time a permanent fix will be available - hopefully soon. In the meantime life on the Bus will go on as normal for those of us who fly it!
Whilst we are at it Boeing never foresaw the rudder hardover on the 737 or the other manufacturers of T tail planes suffering deep stalls so let's not get all precious and sanctimonious about this!
On the Airbus, active (not passive) monitoring is the key!