At my work ~90% of code is now LLM generated. It's not "new" software in the sense that you're describing but it's new features, bug fixes, and so on to the software that we all work on. (Although we are working on something that we can hopefully open source later this year that is close to 100% LLM generated, and I can say, as someone that has been reviewing most of the code, is quite high quality)