Alpha. I can assure you that most professional busjet pilots I have spoken to do not understand that there is a difference.
I have spoken to many about this very point.
In my C208 I have the latest Garmin 750 and it has vertical guidance on the GPS approaches without any connection to the aircraft barometer. The approach can be coupled to the autopilot and it flys the aircraft on the 3’ approach path as well as I can. It is clearly not Baro Vnav. The CJs have baro coupling as well and you say they are not baro Vnav. What are they called then ?