No, almost certainly the other people didn't start the project because they saw his video and were so inspired by the idea they rushed off to build it. Almost certainly, it was a case of parallel evolution where they faced a similar problem and there are only so many parameters in the design space so they figured out a similar solution.

People who focus on ideas think their ideas are so inspirational and unique that they must be protected. In reality, anyone who has tried to go out actively and convince anyone else to build their "brilliant" idea quickly realizes the level of indifference and lack of engagement anyone else has to your baby.