I found an error in my post about private VLANS in the picture of the traffic flow. PC’s that are located in the same community VLAN do have forwarding at layer 2 without going through a router. I have updated
Private VLANs
Private VLANs is a method to segment devices at layer 2 that are in the same IP network. Different VLANs are used but they share a common IP network. The most common scenario for a private VLAN is a residential