[lokeg]

It indeed does not make sense to have a market for carbon sequestration that does not also include fossil fuel emissions.

But implementing a comprehensive cap-and-trade system is superior to a fixed carbon price in that the it directly limits emissions without fiddling with the exact price (which instead is discovered by the market), and therefore can be planned long term.

(What should the carbon price be 2050? That depends on inflation and many other factors, but the allowed net emissions should clearly be zero or negative)

I recommend everyone to take a look at the EU ETS which unfortunately is surprisingly unknown