I've noticed the Meraki DHCP (Nat Mode) states "Clients receive IP addresses in an isolated 10.0.0.0/8 network. Clients cannot communicate with each other, but they may communicate with devices on the wired LAN if the SSID firewall settings permit." in the old UI, where the link takes you to the Firewall & traffic shaping for the SSID.
The new UI doesn't state this but I assume you will still need to disable the Allow rule for Any to Local Lan for wireless networks using that if you do not want them accessing devices on the wired LAN.
I'm seeking confirmation to help assist in providing accurate information to another co-worker.