I segregate using VLANs based on usage.

- IoT

- Personal

- Work

- Kids/guests

- Lab

The first four have their own WiFi SSID.

I don't want various cameras/sensors/lightbulbs that rarely get updates to have access to my personal network.

I don't want to mix personal use with work use (I work from home).

In a similar vein, I trust my kids about as much as I trust random IoT devices.

The lab network is just random stuff, like an archive team warrior vm that I have running.

I could do everything on one single network, but if a single host or device is compromised everything is, and I'm too paranoid to run like that.