@Herald,
In order to have it the way that your "Intelligent designer" could fix the problem, wed have to get into a time machine and head back to the base of the Cambrian and start stomping out all the newly evolved animals that utilize CO2 to form shells of CaCO3.
Whether the post Cambrian declines were related to continental drift forming shallow ocean basins and vast colonies of "CaCO3 life forms" We have hit upon several times in earths history where CO2 almost was gone due to Ice sheets absorbing and holding CO2 in "Ice sinks". During the Triassic continental glaciation, the angiosperms plants arose (especially the grasses)
Also, during the Pleistocene the decline of CO2 wiped out much of the broadleaf forests and grasslands took over.
You should look up the difference between C3 and C4 plants and how each utilizes the Calvin -Benson cycle in their photosynthesis.
We can see fossils of grasslands that correspond nicely to glacial epochs.
IS it that you are worried that broadleaf plants will disappear from the earth as the CO2 level disappears?
Ive alwys been a skeptic on anthropogenic global warming based upon this very point.But I don't see any evidence of an INTELLIGENCE, quite the contrary, I see compelling examples of how life colonizes niches based upon "Their comfort zone"
When CO2 saturation was achieved as 10% of the atmospheric gas, CO2 was available for colonization by all sorts of animals with shells (Ca Tests) , when it decreases to where it is today <.5% the seas begin to extract back the CO2 from the very animals it helped evolve. SO the large shallow coral beds (See Great Barrier Reef) are actually dissolving due to CO2 getting close to the 1% limit.
lo, the rise of C4 plants so nicely corresponds to glacial advances where forests of broadleafed plants die off.
Evidence abounds showing us that such a series of earth cycles have been in play over the ages