Yes they're longer. Glock has redesigned their magazine tubes several times, the tubes were made slightly longer in the late Gen3 magazines. Gen4 magazines are identical to the late Gen3 magazines except for the extra magazine catch cut-out.
They made the very top of the magazine tube slightly slimmer and more tapered from some reason, and I assume the result was that they had to add an extra few millimeters in length to keep the same capacity.
I have a couple of G23 magazines from around 2003-2004, and setting them next to the newest magazines the feed lips and magazine catch cut-outs are exactly level with each other, the bottom of the newest magazines extends slightly further. Maybe 2-3mm
