Why is a mechanism needed to remove carbon dioxide gas from your cells?

A mechanism is needed because if carbon dioxide were to simply diffuse into our bloodstream to be carried all the way to the lungs, carbon dioxide would dissolve in our blood to form HCO3-, which is acidic and decrease the pH of our blood. This would be fatal for us as our body needs to maintain at a relatively neutral pH. Hence carbon dioxide is removed via hemoglobin from our cells

Respiration is responsible for removing carbon dioxide and providing oxygen to our body cells. Carbondioxide is eliminated from the body as a byproduct.