It’s literally a 75mm AT gun shoved on top of an armored personnel carrier.
The APC has armour which means it doesn’t instantly get blown up. As a result, Gaijin will add it as a premium in the future
For Na-To they can just use the model from War Thunder.
But you need several modification to turn this vehicle into APC.
Moreover this vehicle is armored, currently all tech tree APC are not armored.
This vehicle is not actually designated as armored personnel carrier, but a tracked truck. There are better alternative like Ho Ha and Ho Ki which are really designated as armored personnel carrier.