If you just cut the top (and it becomes like a #16), then there will not be a cutting edge on the top view. Then you have to redo the upper blade, it's already harder to replicate the original finish + it takes a lot of skill to remove the painted metal neatly, 1 mistake and knife is spoiled (outwardly, for work it still suits).

p.s.
I took one of the photos of the old Astro of one of the members here to show the difference. I hope he does not mind, if not, I will delete the photo and apologize.

p.p.s.
I think I understand why the word replica was used for a while, the original had a very large guard and for non-astronauts it would be very uncomfortable (If only a person is not fond of medieval weapons and uses it))