Somebody else has already said it, they have the blog post, beat you to the .com domain name, they have the app, or created the youtube video.
There are so many that don’t know. They have never seen it. You can influence them, be the saint of good news, save their day with your words. The ones who came first do not matter as much as you think. They don’t have your flair or panache. They way you write or present the topic might just very well be different enough that many others might just “get” it after seeing your content.
Plus it’s also about you. People do not know about all those articles you have read about a subject. We do not know how much of an expect you are. Someone out there is looking for someone to help with a topic you know a ton about. But they never connect the dots back to you because you are not talking about it. It will take more than 1 article or blog post. Just keep creating.