The only time that using carbon dioxide is worth considering is if you're forced to use an arbitrarily high TA (80 +) and an arbitrarily low pH (7.4 or lower).
In that case, you're in a no win situation.
It creates a lot of carbon dioxide in the water that offgasses and raises the pH.
If you reinject carbon dioxide, you can maintain a stable pH and TA.
However, the cost is high and it's really a huge waste of money.
If you're allowed to use a higher pH (7.8 +) and a lower TA (60 or lower), you can minimize the amount of carbon dioxide in the water and the associated pH rise from offgassing.
Even if you do use carbon dioxide, maintaining the pH as high as possible and the TA lower can significantly reduce the amount of carbon dioxide needed.