There is existing, and there is being effective for the advertised job. Carbon capture certainly exists in different forms and makes sense as an addon to an existing emitter. It's hyped to be a lot more than what it does, even used to excuse more emissions growth, and that's the snake oil being talked about. In the end the only true "solution" is to reduce the actual production of emissions, something that the overall world is not will to do. And I put solution in quotes because we're decades behind on action that would be meaningful, having exponentially increased the pollution since then. We'd have to do far more than just stop emissions to fix anything.