it's possible it is only on knox enabled devices. looks like m31 does not have it.
www.samsungknox.com
tbh it's not really that big of a deal. the problem with whatsapp is not that it is stealing information from your other apps like a malware app. i am pretty sure android these days is locked enough not to let it happen easily.
Device Compatibility Knox Solutions | Samsung Knox
See which of Samsung’s flagship smartphones, tablets, and wearables are built on the Knox platform. Knox is currently available on most Samsung Android and Tizen devices.
tbh it's not really that big of a deal. the problem with whatsapp is not that it is stealing information from your other apps like a malware app. i am pretty sure android these days is locked enough not to let it happen easily.