There's an old saying in startups: "being early is the same as being wrong."
And it's true.
For every huge successful startup you can name, there's someone who tried to do it before and failed. Sometimes they failed on their own, but often they failed because they were just too early. They had everything but the market just wasn't ready.
It must be the worst thing ever for these entrepreneurs to watch others make billions thanks to an idea and product they had. But that's life.