That sounds about right, as someone who started and runs their own company. Having a decent idea for a product, being able to learn and having experience are good skills to have but they are not important towards the building of a company and leading a team. You could potentially build a product in a niche area, but you're not going to build anything beyond a very small business with those skills alone.
Running or building a company is about allocating capital, hiring good people and being able to manage them effectively, and being comfortable with delegating tasks to competent experts instead of trying to micromanage everything. That's how you get scale.
If you don't have those skills, nothing wrong with that, most people don't. Instead you find an existing company that has that, and you join them and offer them the skills that you do have.
One thing you quickly realize when you start a company is just how chaotic it is in ways you never expected from legal aspects, financial aspects, coordinating things internally within your company and externally with third party vendors and your customers, and you begin to feel the pressure of having competition that is constantly trying to shut you down, especially as you get bigger and bigger. It's very fierce and you are reminded that every single dollar you make is a dollar that someone else is fighting for.
If what you want to do is focus mostly on a product and employ your particular area of expertise then do not start a company, join one. Finally this extravert vs introvert stuff is nonsense, don't use it as an excuse or let it deter you. Plenty of introverts are incredible leaders that have managed to run some of the most wildly successful companies ever known. Look at some interviews with tech CEOs before they became successful; they are some of the most socially awkward and uncomfortable looking people you can imagine who seem to really hate giving talks, heck check out the infamous Zuckerberg 60 Minutes interview or other interviews from around 2004. Early Bill Gates interviews are only slightly less awkward as are interviews with Google's Larry Page.