> Apart from the Linux kernel and web browsers/tools, it is perhaps the only open source software that managed to beat all the commercial software in its niche.

I can think of a few more: Git obsoleted an entire category of commercial software seemingly almost overnight, VSCode has become by far the most widely used IDE (not entirely open source, though), TeX still dominates mathematical typesetting AFAIK (as it has for as long as computers have been used for that), (lib)ffmpeg is used everywhere for video/audio transcoding and between them nginx and apache still account for the majority of webservers. Most popular programming language compilers/interpreters/runtimes are open source too, of course.

OBS smashing XSplit comes to mind