When we get access to the internet, we train our brains to only prioritize immediately relevant information and not access old memories. The interesting thing is that if you stop using computers for a while, all those old memories can be triggered at some point. They aren't forgotten, your brain is just in a different mode while you have access to the internet.

This actually leads to the culture of constant discovery and discovery engines on the internet. We're always onto the next article or video or what have you. We "forget" as quickly as we accumulate new information.