Whether people merge early or wait until the last minute, the same quantity of cars need to merge. Waiting until the last minute just gives more room for mistake and need to slow down and confusion between vehicles trying to merge before they hit a wall.
I think most zipper merge people are just trying to justify cutting in line. If anything I think waiting to merge before hitting a merge wall just raises risk.
Someone walk me through the math and how merging later saves time. All cars have to wait in any case. Whether the assembly line is sooner or later, the timing doesn’t really change.