I don’t recall ever hearing that specifically

Somewhat similar though, I remember being told that anything you put out on the internet is out there forever. Which may not technically be true, there’s a lot of lost pieces of internet history, but the core of that statement isn’t really to be taken literally, it’s more that once you put something online it’s out of your control what everyone else who might have access to it does with that data, you can’t really control what people download, screenshot, save, repost, or when it may resurface.

But back to what you’re saying - even with China and Russia, and other attempts at censorship, the internet still carries on. You can take down, wall off, censor, etc parts of the internet for a lot of people, but taking the entire internet down would be a massive undertaking, probably more than what any country or even any realistically feasible alliance of countries could hope to achieve, as long as there are people with computers linked together somewhere, the internet endures in some fashion.

There’s a lot of redundancy in the internet, there’s no one big box to blow up or one cable to cut that carries the entirety of the internet, it’s millions of devices all linked together in millions of different ways that make up the internet. You can take down parts of it, maybe even most of of it, but it would be nearly impossible to never every last thread of the internet without some truly apocalyptic event happening, even if all that’s left at the end of the day is two nerds on opposite sides of the planet with ham radios hooked up to laptops sending emails back and forth, or some friends sending memes back and forth on thumb drives via carrier pigeon, you could still say that the internet is alive, if not exactly thriving.