Same skill-set as for any business endeavor (for example, Protonmail's or Mullvad's businesses are based on an open protocol, they seem to be doing OK). At minimum, you need a vision, the right people, data to help you monitor your progress and manage your costs, while being ultra-focused on your target users and how the solutions you provide can generate cash flow for your business.

As @Natalia mentioned somewhere, it's all about small incremental experiments, and survival. It's not easy, stressful, but probably the best way to feel alive and contribute the changes you want to see in the world, without asking for permission.