Great article. I really appreciate that the OP describes a more closed-form solution to what makes a senior engineer, rather than platitudes like "learn 5 languages".
One nit I'd pick with it though is that many large and bureaucratic companies won't appreciate an engineer who decides it on them to fix hiring, culture, product marketing fit and marketing. If you find yourself in this position, it's time to move on to somewhere else that will. Typically, those companies are startups.