I have never had that happen, so it’s not normal in that sense. In the sense that it’s the property of the ISP and you are renting it - yeah seems completely normal. They don’t want people messing with config, or they want you to use another method like calling support.

ISPs in the US can harvest and sell your web browsing data. They don’t want you to do anything to endanger that.

Why not track how many network calls to and from IP addresses you can geolocate to China you actually see before doing anything? Geolocation using IP is far from perfect