That's not too accurately summarized. In the linked text they promise to not sue individuals participating noncommercial open source development related to cert

That's not too accurately summarized. In the linked text they promise to not sue individuals participating noncommercial open source development related to certain covered techologies, which are protocols, languages, file formats and standards. A huge amount of stuff, both technologies and contexts, is left outside the pledge. Thanks for linking, though; I never bothered to familiarize myself with this before.