New network... can't ping or access anything

Hey folks… I just setup a new network and added a few clients. I left the default routes and flow rules in place, just as I did for a previous network.

The trouble I’m facing is that none of the clients can connect with each other, and by “connect” i mean ping, ssh, vnc, smb etc… everything. I literally have no connectivity between clients using any method or protocol. The firewalls are NOT enabled.

What am I missing?