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You are mixing up the units here. Value is not a real money, and you can’t pay salaries with value. You can pay salaries with cash.
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To actually get how many LOC in a kernel per person per year they produce. You need to look at git history, and do data science on it. It’s doable and easy but not really my area of expertise.
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You need to account for that vast majority of contributors make just one patch and they are never heard from again. They don’t work full time, or even part time on the kernel.

You don’t need a video. You need marketing & communication 101. During covid I am sure some professors uploaded lectures to youtube, or pick up the book if it’s more your jam. Think about what you want to communicate to a person coming across your project for the first time. Make bullet points and rank them. Then begin writing including all the information in that order.
A good readme would be sufficient. Go to some popular project and copy their structure of its readme in your project.