@Utterlybananas333 Is it just the fact that children and adults don't talk anymore? That nobody reads anymore? Or even watches educational TV programs? Would your child know?
Here's my own take on this (someone else has probably already alluded to what I'm about to say).
When we were children, and we were bored, we would have read whatever book was available, or read whatever magazine was available, or watched whatever TV show was available. Because we were engaging with whatever media was available, rather than the media we actually wanted, that meant we were hoovering up lots of random knowledge that we never would have been exposed to otherwise.
Nowadays with the internet, children only engage with media that they want to engage with. They won't watch a random show (for example) on space and astronomy on TV intended for a general audience, and instead, they will just watch videos about children's games like Minecraft and Fortnite, because they are able to see these at any time. So because children are engaging with media in a much more targetted way, they have lost a lot of general knowledge that previous generations would have had.
As for the word "velvet"... as a child, I picked this up from the Galaxy advert. Why have velvet when you can have silk? Again, random knowledge acquired from watching TV.