I had previously a Sony Xperia Z3c (and now a Google Pixel 4) paired with my GW. I understand that with a Samsung phone the watch synchronizes more data with the phone. Such as Reminders and Alarms. For me these are separated and so are silent modes. Calendar data is automatically transferred from the phone to the watch. The watch can use the information (both native Calendar and Watchmaker watchfaces), but I can't edit on the watch. SMS can be replied to and created from the wath.
I can read email content but not edit.