So these are not some dusty forgotten thing from history books that people might read about, it was stuff they saw on TV and is back in the news whenever a round-number anniversary comes up etc.
The point I was trying to make is that quite shocking bad things happened semi-recently, and more shocking bad things continue to happen. It appears in the news over and over and over about people being radicalised online.
I get why people think this is a good idea - you need to prove age to buy knives and cigarettes etc, so they think "why not" for porn and other "adult" things online.