>>16136616Look at their wiki pages.
The majority of holos are between 150-160cm
Marine is 150 and Miko is 152.
There are, in total, 9 holos below 150cm with Laplus being the shortest at 139cm followed by Luna at 140 then Gura by 141 (yes, Luna is actually shorter than Gura).
Kanata is actually the tallest among the shortest holos being the only one at 149.
I think Reine is the only one who's 170+, even Mori and Kiara are only in the high 160s.
The answer is because the average height in Japan is short so their fictional characters reflect this.
Look at anime character heights, it's the same thing.