The internet _as the Western world knows it today_ will not be the same in a few decades. But then again, it's hardly the same today as it was 30 years ago either.
A few things affect this:
- Advertising. It's everywhere and corrupts every form of media. Content is made to appease advertisers, and web services are built to extract data from users. The internet experience is getting gradually worse.
- Politics. For some reason, it's only dawning on governments now that providing uncensored and unfettered connections to their political adversaries can be used for information warfare. The idea that connecting the world will make it a better place and undo the millennia of tribalism is a romanticized platitude of the 1990s.
- Artificial intelligence. The situation will only be exacerbated by letting AI loose on the internet. Whatever humans can do online, AI can do much, much better—or worse, depending on your perspective.
The outcome of these things will be that countries will have a more restricted and censored version of the current internet. We'll follow China's example, and have a European internet, US internet, etc.
The internet will survive. It will just be very different.