With a crack running up the tube I’d be asking them about their layup schedule. I’d expect the outer layers on any seatpost to be bias wrapped, there’s little strength to be had from fibres running straight up the post, especially when almost all the experienced load is front to back. +/- 45 degrees is order of the day.
If they’re really on their game them the trailing edge of the tube should be thicker than the front and the front thicker than the sides.Assuming a relatively normal saddle position most of your weight will be over the middle/back of the saddle and hence leverage comes from behind. No matter how much you might try you just can’t support as much weight on the tip of the saddle as you can the back and they should design accordingly. Look at a Thomson, their wall thickness distribution tells you all you need to know.
If they come back telling you it’s just the beauty layer ask them why they don’t use a beauty layer that offers structural benefits, after all it’s a top flight light weight component, there’s no place for ‘excess’ anywhere.