Those examples aren't actually capturing carbon from the atmosphere. They're capturing carbon produced as a byproduct of industrial processes. There's a massive difference when you're already working with concentrated carbon dioxide and when you're trying to capture it from the atmosphere.

If it’s capturing co2 that would otherwise go into the atmosphere…does it matter ?

It makes the burning of fossil fuels more efficient, e.g. you can X tons of coal to produce Y MW of power and get Z additional gallons of gas. But it's really a stretch to call this carbon neutral.

There are other processes that produce CO2. E.g., cement manufacture.

Yes, because Prometheus fuels is trying to extract from atmosphere. Scavenging industrial CO2 byproduct is something you can only do opportunistically.

There are plenty of opportunities. Those will be taken up first.