It is pick your poison. Extending out the three point line makes it a harder shot from outside, but also extends out the defense. It becomes much harder to rotate back down to the corners, even with more athletic forwards we would be hard pressed to trap successfully anymore. The zone used to be a more effective defense because the spacing was tighter, and it forced offenses to be more pass focused.
Unfortunately, to play a good man to man defense you need athletes who can keep up with their opponents. You can maybe get by with having one teammate who is slow footed but a great shooter. Having two or three however means trouble all over the court.
Botttom line, unless you are trying to press, creating a trap in the corner is becoming harder and harder to do regardless of which defense you use.