Makes more sense when you think of it in terms of Google both getting to control the standard and getting to shove their libWebp binaries into Firefox, Linux, Mac/iOS, popular image processing libraries, etc etc (oh but HURR DURR IT'S OPEN SOURCE yeah that doesn't matter when every project just uses Google's source code without looking at it because Google generously made it a complete turnkey solution you can just import. This isn't even a hypothetical, Google has already managed to backdoor literally every device that uses it and it had already been exploited by their darling Israel for ages before someone outside of Google discovered it, you expect me to believe it wasn't intentional?). Like so many things in the tech world, it's not for your benefit, it's for the corporations'.