Question about Sharkoon Skiller SGS2

I am 168 cm and it is comfortable. The neck cushion can be moved down well.

I am 1.86 and had to buy a footrest even for the lowest setting.

I suspect it is not suitable for 1.65, as the lowest seat height is quite high in my judgement. at 1.65 you will not be able to place your feet ergonomically correctly on the ground without resting your feet on something.