A big argument for carbon capture and storage is true reversal; while switching to renewable energy and eliminating CO2 emissions is a must, it will not reverse the massive movement of carbon from underground hydrocarbons to the atmosphere and biosphere.
However, prevailing strategies are not exact reversals of burning fuels, either. Rather than converting CO2 to hydrocarbons to be buried, CO2 may be directly injected deep into the ground or converted to carbonates first. Would there be consequences for the biosphere if we do manage to bury 2-3 oxygen atoms for every carbon atom that will also be buried, that so far would have been released into the atmosphere?
EDIT: For the sake of argument, let's assume a hypothetical method of capture and storage that uses only renewable energy and that the buried matter does not leak back out. This question should not be construed as an endorsement of current carbon capture and storage technology.