Intracity buses have cameras. Intercity buses require ID.

No they don’t. I’ve often put my kids on intercity (really interstate) buses to go visit their grandparents. I’ve never had to show ID and they don’t have ID.

Did you show it when you bought the tickets? Which bus line?

I remember news stories about it, and thinking that people could no longer travel anonymously.

These are private bus lines like Flixbus.

They require ID here in Europe. They don't always check for it, but probably they want to avoid delays in case the bus is checked at a border.

Are there public interstate bus lines?

Public? No. Though, the one most people think of is Greyhound and maybe they do check ID. I was just emphasizing that I was not using Greyhound.

Why? Do interstates also have border check points?

Bus companies require them, afaik.

Real criminals ride bicycles.

And don't carry ids or phones.