I mean, if we decided to build everything from scratch using only the OS and a programming language, we wouldn't be building any products. Recommending using a hilariously basic log (straight to file, no modules/level control, no buffer to avoid performance hits, no multithread support) instead of using a established library for logging is pretty naive. Yes, one should know that dependencies can introduce security problems, but the protection against that is not "remove all dependencies and build everything yourself".