The use of raw-usb and raw sockets look to be core functions for the rtlsdr snap and network-observe is the least-privileged way of granting permission to use raw sockets within snapd. As such, +1 for auto-connect of both raw-usb and network-observe for rtlsdr.
+1 from me too for auto-connect of raw-usb and network-observe, given that this snap requires usb access to the device for signal capture, and network access for core functionality.