As someone, who has experience in building and selling open-source businesses, I cannot agree more

Open-source can be a great selling point and a growth driver, but it won't replace all the other parts of running a business, such as marketing, sales and most importantly, a functioning, profitable business model

If you need some advice, feel free to e-mail me

I will take a look at your open-source project and tell you how it can be turned into a business