* https://en.wikipedia.org/wiki/Short_(finance)#History
Bond markets started early than that:
* https://en.wikipedia.org/wiki/Stock_market#History
The judgement of the value of this I will leave to others to decide.
My point was almost consonant with yours - it's almost as old as stock trading, but nobody realized how fundamentally different the concept is. They didn't realize it in 1609, and they certainly don't recognize it now.
Most naive conceptions of how stock markets work would never allow for these sorts of contracts. The fact that they've (nearly) always been a part of actual stock markets just points to the same sort of gaps between the actual operation of the financial services industry and how most people think things ought to be that the current GME gyrations are (according to some) also pointing at.
Neither is it "radical" in any type of market. It just means selling something you don't actually have yet (something you're "short"). Think of a middleman who sources classic cars. He contractually agrees to sell a 1991 Ferrari for $60k. He doesn't yet own the vehicle, but knows he can source them for $50k. Unfortunately for him, a recently popular meme has gassed the price of Ferraris, and he now has to pay $70k for the car. He's still obligated to sell at $60k, so he begrudgingly takes delivery and loses $10k, having "sold short" the car. Is he revolutionary or radical?
They also serve quite different purposes for a society/economy.
Futures are useful to a broader group of people precisely because they don't need to involve physical settlement. Many people use commodity futures to hedge exposures to the price of assets which are not the underlying in the future but where there is a relatively predictable relationship between the two prices. Others use them to speculate on prices despite having no ability to deliver or take delivery of the underlying. Some contracts are even purely cash-settled.
(Edit: made clear that it was the point that futures always involve an underlying which already exists I disagreed with.)
Not to contradict you, but just a reminder that short selling is based on something significantly different than "trading and holding stocks". The ability to promise to buy/sell stocks in the future at a given price has become so accepted as an ordinary feature of stock trading that we generally cease to notice how revolutionary of a concept it actually is. It's hard to see any rationale for prohibiting such arrangements - they are entirely consensual, and appear to have no additional impact on things that instantaneous buy/sell orders wouldn't also have.
But this is an illusion. The ability to go short/long on a stock is completely different from the ability to buy/sell it, despite it being based on all the same mechanisms. It's a truly radical concept that has slipped under our radar because it could be described without any new concepts or terms.