Lacing dates back to the beginning of electrical wiring (late 1800s, early 1900s)
a) "Zip ties" were not invented yet (nylon was invented in 1935)
b) Twisty ties are thin metal wires covered by paper (plastic covered ones were not practical until the late 1900s). The twisty wires were a threat to cut into the wire bundle. They also rust.
Even in modern days with zip ties, lacing has a significant advantage in that zip ties have sharp "tails" that stick out from the bundle and cut your hands and arms when you reach into a compartment. Lacing lies flat against the bundle and has no sharp ends.