Huh, didn't know that.
Still, I think that the origins of chainmail (coming out of medieval wargaming) would have eventually been developed by someone else, and that would have eventually led to D&D. Heck, it may even first happen in video games and move over to tables later. I don't know, but I'm skeptical that if Gygax was never born a different TTRPG would never emerge.
Now, emerge to prominence? Less certain about that.
We have an American Flag on the Moon because the Dukes of Burgundy came up with the idea of Credit.
The Dukes of Burgundy came up with the idea of Credit in the "I have a line of 'Free Money' based on what you anticipate I'm worth that I can spend now and pay you back at a later date.". This allowed them to put more soldiers on the field of battle with better equipment, particularly cavalry and armor. As a response, the Swiss created the Pike Square formation. The Pike Square didn't require heavily trained or armored troops to perform. You just get a large number of peasants together, put them in a square, put the Pikes outward, and suddenly you've got a box that cavalry can't easily overcome.
Hundreds of years later, the Pike Square is used to great effect by French Revolutionaries in France, that and the loss of most of the military leaders to the guillotine (along with all the other leaders) leads Napoleon to decide to have MASSIVE armies that can protect his cannons with their feeble meatsack bodies! Allowing his bombards to destroy fortifications and troops while keeping his cannons safe from cavalry. But this caused Supply Chain problems.
It's expensive and dangerous to feed an army. So Napoleon entreated his soldiers families to send them food on the battlefield. The common response to this, for a bunch of -very- French Parisians, was to bottle food in empty wine or champagne bottles, put the cork in, and send it out. This worked pretty well, but sometimes the food would be spoiled by the time it got there while tinned food didn't. The French chalked it up to "Bad Air" from the swamps around Paris and mostly focused on getting tinned food to their soldiers.
The "Bad Air" theory carried on. And when Malaria was a problem it was theorized that the "Bad Air" of places where Malaria occurred was the -real- problem. So a doctor in India asked one of his friends to send him "Good Air" to use from Switzerland, where Malaria didn't occur. By pressurizing air in a metal container the air got colder, which lead to the invention of Air Conditioning. Which, while not a cure for malaria, helped to keep people alive as they fought off the infection so it was "Good Enough".
In the late 1800s a scientist wanted to try and mess around with Air Pressure because air conditioning was a thing and compressing air made it turn cold. So he created a way to put a Vacuum between two pieces of metal to see if the heat and cold would transfer across that empty space. It did not. And thus he invented the Thermos.
Then a couple of geniuses realized that putting a Thermos full of Liquid or Solid Fuel in their rocket allowed the fuel behind the vacuum to remain relatively cold while the fuel being burned off was incredibly hot and that's why the Saturn V rocket allowed a man to reach the Moon.
History is so naughty word weird, man... It's -so- weird...
