There are several threads about the A321, not just the NEO, having a "delicate" weight and balance problem.

This is then covered up by software and training of the pilots.

The A321 is an "overstretch" of the A320 similar to the Max being an "overgrowth" of the 737.

In both cases the airplane companies have taken the basic airframe farther than it would normally have gone, aerodynamically, through the use of software.

In the hands of well trained pilots, this is not an issue.

The issue is the decreasing number of pilots who are actually familiar with flying airplanes rather than flying computers in airplanes.

The massive growth of the airline industry has led to pilots with very little stick time in the cockpit, compared to past generations.