“Turns out, TP-Link thinks it’s a great idea to have hidden pre-configured always-on networks on all of their routers.”
His router broadcasts two hidden networks he never set up and can’t turn off. They don’t show in the admin page. TP-Link put them there in case someone buys its OneMesh product. The fix is a slow beta firmware rollout, two years after users first complained. You bought the hardware, and TP-Link still decides what it transmits.