Most people are using routers given to them (and configured by) their ISP... so really they are blackboxes connected to an upstream blackbox for most people.

I am always surprised by how many people give me their ISP chosen router name and ISP chosen password when I connect to their WiFi. I don't want to give my ISP that much control.

Are you really surprised though or are you talking about the HN reading subset of your "many people"?

Coz I would absolutely 100% not be surprised for your average consumer.

For your average HN reader I would hope they treat whatever their ISP gave them as just some dumb "switch" type device that sits outside their trusted network and handles nothing but encrypted traffic. Like my ISPs device definitely does have a WiFi and such, which I disabled. I treat it as a bridge / modem and it's definitely not part of my "inner circle". Hasn't been in 25 years.