A rising tide may not lift all boats. Let's say that rather than giving your hybrid to all neighbors, you give it to the world. Now everyone in the world raises yields by 50 bpa. And now, you've glutted the market and the price per bushel is so low no one makes a profit, so the farmers go bust. Or the farmers agree to destroy commodities to keep the price up. That happened with dairy products during the great depression. Dairy farmers produced too much, prices collapsed, farmers could no longer buy feed for their cattle, and went out of business, destroying their herds in the process. This brought about farm price support programs.
The moral of the story? If you want a rising tide for boats when supply increases, demand has to rise, as well. As you have failed to address the demand side and assume an infinitely elastic market, you lose, economically-speaking.
Next time, we'll introduce you to the concept of inequitable distribution of market gains, so you can understand that rising tides do not lift all boats equitably, so even if a rising tide does raise all the boats, a majority of the fleet's captain's can still all feel poorer as a result of the process. Remember that, at the core, we're still dealing with human psychological processes here. Even if you raise the boats, relative level matters - especially if you want to look at rational models of effort vs. probability of reward.