Your 2016 CX-5 Sport has original SkyActiv-G 2.5L (or 2.0L?) NA which has fairly reliable cylinder head. Mazda has modified the head to accommodate the components added for cylinder deactivation to the 2.5L NA since 2018, and IMO which has weakened certain areas on original cylinder head and hence the crack issue. Similarly Mazda modified the original cylinder head on the 2.5L NA for turbo and it has also weakened certain areas on original head and hence crack issue. To me, both issues are design issues, and the problem won’t go away unless Mazda redesign or modify the head to reinforce the crack areas. Yes, 2.5T seems to have more cracked head happening, and Mazda has actually modified the head, but it’d take several years to prove the modification is effective.