I think lasers are pretty wack when you think about them through this lens. A small, wand-like object in your hand can make light appear from seemingly nowhere. If it’s powerful enough it can set things on fire or blind people. Not to mention larger ones like laser cutters or the LLD, used to destroy missiles midflight. Thats sure to blow some feudal peasant minds
Honestly, I feel most things would depending on how far back you go:
If you’ve only known stairs your whole life, a lift would seem like a teleportation device.
If you’ve never even seen a wheel, a car would look like a loud metal monster.
If your whole world has been the one village you grew up in, the Internet is just plain incomprehensible.
If you’re used to making fire with a flint, a simple lighter (especially one without a flint in it) would seem like a magical device already.
Now, I’m not saying you couldn’t explain these concepts to them. People in the past where far less stupid than we often think, they just didn’t have the vast knowledge we currently rely on. But if you where to show these things to them without any context, they’d probably think you’re a witch or something
I somewhat disagree. As you said people weren’t idiots, they just lack the contextual understanding we have.
Take a car for example. Even if you’d never seen a wheel, it would surely be easy to understand how it works just by seeing a car roll by. You may not immediately understand how its moving itself but I don’t think that means you would conclude its magic. You could think it’s biological, but honestly concluding that it’s a machine doesn’t seem that unlikely to me.
Also the internet… I think most modern people just think it’s magic really.
I once talked to a guy on Reddit who had a version of this turned up to 11.
I don’t remember the exact times so I’ll guess but it’ll get the point across.
He boarded the New York Subway at 8:42am September 11, 2001, and got off at 8:50am.
Dude was just having a normal day walking onto that train and the next station was in a totally different dimension.