Ask HN: Why Sabatier reaction is not used in need for optimal methane synthesis?

As I am studying some chemistry for one of my main projects, I was curious why Sabatier reaction producing methane from CO2 and hydrogen is not used on a wider industrial scale for methane synthesis? Can't an appropriate startup leverage some AI for cost-effective etc methane synthesis optimization?

[1] https://en.wikipedia.org/wiki/Sabatier_reaction