And went nowhere for 100 years.

I just finished saying that initial prototypes do appear for decades before the item can be rolled out in volume. Inventing something is only the first hurdle; often the easiest hurdle.

There are many more hurdles involved in mass-deployment, and those hurdles often require inventions not in evidence yet. It's not enough to invent something. You have to invent and develop every single tool, process, manufacturing and logistical item to mass-produce the thing in volume, safely, and with all consumer issues addressed.

When your articles start addressing that, we'll reconvene.