I miss usenet and webchats, mostly, and the fact that communities were smaller and you could feel you could actually contribute. Now it feels like you can already find what you wanted to say. And the opposite of it.

What I Definitely don’t miss is: popup with ads, the <blink> HTML Tag, the “under construction” images on websites that would never be updated ever again, and images that would take minutes to download.

What I know I will miss from 2020 in 10 years: contents written by actual humans instead of AI.

It took me quite some time to understand what OP was talking about…