The point of a carbon tax is to fund and/or incentivize research into non-carbon energy production, or carbon removal technology. If you just offset other taxes, for a tax-neutral result, then there's no (macro) tax incentive so how does that happen?
market competition leads to better manufacturing techniques that avoid the tax. Local optimization leads to global optimization. To argue otherwise would be to argue that taxes overall have no effect on business behavior, which is clearly false.
