No they are not. Most people can't explain off the top of their head how the derailleur works to move the chain from one cog to another, or how freewheeling allows the wheel to move without the pedals to move, or even how the cable allows brakes to be remotely activated from the handlebar. Most people can't even explain why it is possible for a bike to be stable while moving but can't stand on its own. It's counter-intuitive.
There's plenty of ingenuity in the design of a modern bike.
Most of what you're describing isn't necessary for a bike. A fixie bike doesn't have a derailleur or freewheeling. And you can slow down without breaks.
You can even remove the chain. A penny-farthing bike is a surprisingly simple device. It is surprising it wasn't invented earlier.
My guess would be that they weren't invented earlier because they are not that useful without good roads.
There's plenty of ingenuity in the design of a modern bike.