Yeah, I agree. The initial stages of releasing to public is always rough. You need to gain traction and be able to capture a suitable audience who is willing to use the product. Unfortunately open-source projects are not some product you can make ads on and show it on TVs or billboards. But thankfully there exists platforms like Hacker News and Reddit. Two good platforms where you can post about your product. While its more specific on Reddit, you need to share it on a subreddit you think whose audience closely resonates with your project.

Once your project becomes popular that's usually when companies start looking at it. And when you reach that stage you probably already have established a community for your project.