Neil deGrasse Tyson explains that the CO2 in the atmosphere is absorbed by the oceans until they reach equilibrium. If we stopped burning fossil fuels today, the CO2 reduction in the atmosphere would cause the CO2 to come out of the oceans for a very long time in order to reestablish the equilibrium. So it will take a very long time to see a reduction in the CO2 in the atmosphere just like it took more than a hundred years to build up.
https://youtube.com/shorts/eRzUJOGIrTY?si=EyMepjQ4KMv5UFhJ