It seems far more likely that we'll end up in a state where you won't be able to override CSS at all. You'll be allowed to use only the most modern version of Google Chrome because all the websites will simply require a private auth key that only Chrome possesses, and commands like cURL will no longer function properly. The devtools console will be locked behind a key that you must petition Google to get, and if you use it for anything other than what they want, your permissions will be revoked without further recourse.

I've had similar thoughts but replacing Google with Apple who I could easily seeing doing parts of this. They have the platform stranglehold and abusive history to support the behaviour and current browser "enforcement", with little to nothing in the way of consequences.

It’s a very sad future, but totally plausible at this point. We’ve got to fight this.