Not confusing.
It's a pistol with a brace until someone tries to make it more like a rifle stock by perm attaching or removing the pesky strap or doing anything else to make it more comfortable to shoulder. If a pistol with a brace goes near and/or touches the shoulder of the shooter, it does not re-manufacture the firearm into a rifle.
Just don't put a brace on a pistol with the intention of using it like a stock. If it happens to touch your shoulder during use, then don't worry about it.
Now people just need to stop worrying about this non issue, as well as not to try and "purpose" braces as designated stocks on their pistols.
End of conversation.