How to Reach Out to Community With Open Source Projects

I love talking to early stage companies or just dev tools open source projects about like, how do you get started in reaching out to community? And consistently everyone's they bring up their slack channel and like, Oh yeah, we have 2000 or 7000 people in slack. And I was like, Are you sure? Like, because it just seven thousand people in a slash channel is like that it is a lot of noise. In reality, like it'd be so much easier just to funnel those folks into the comment thread of a blog post or funnel that to your Twitter instead. Because at least that signal, it's SEO driven or that signal is like discoverable.