Sometimes it seems as if the support technicians do not have knowledge about computer systems and only follow written procedures in a manual. I am an enthusiast of embedded systems, firmware and software, I am far from knowing everything but I am working on it and many times public information about the new technologies incorporated by microsoft is lacking.
I am glad to be able to resolve your concerns, you are right to think that it is a mistake since Microsoft released this feature from Windows 8 and never communicated or taught about it.
In my case, the modern standby feature allows me to keep track of emails or calendar events even when I have the equipment suspended, it also allows me to wake up the equipment using a bluetooth mouse or keyboard thanks to the fact that the wireless card continues to operate when found suspended. It is something like having a smartphone always on but with the screen off.
Microsoft strives for its surface equipment to offer a different and professional use experience. This characteristic demands a great effort because many components of the computer system have to tune up. This is the reason why many manufacturers prefer not to incorporate the functionality, in addition to requiring premium components to be able to offer it.
And of course I am aware that many times they release updates that only make the system worse.