IME skill-stacking (and including something rel to people / human interaction in your wheelhouse) is the best path to [power / authority / autonomy / clout / leverage]. It doesn't have to be binary "tech or mgmt". But you're absolutely right; companies are groups of people. If your role is such that your influence doesn't extend beyond what you can personally code, your sphere of influence (and career opportunities) will by definition be limited. This can be mitigated by eg explicitly developing skills of presentation and persuasion... but if you work somewhere that has other employees, and don't want to get stuck in a downstream role slinging code, there is no alternative to learning and mastering the [human] interface to the rest of the company.