One huge problem is that contemporary, technological warfare (except for minor complications like drones on air and water) is largely based on air supremacy, or at least superiority.
The West has felt itself constrained in offering the extended systems that allow Ukraine to seriously control their skies. We have said we are giving Ukraine F-16s in numbers that are essentially performative, but not in the numbers (or with the equipment) that could support the fleets on A-10’s we have moldering in our deserts, a weapon designed for just this problem against this very opponent.
Without total air supremacy to protect them, A10s are slow fat juicy targets to an enemy that has modern air defense weapon capabilities (like Russia). They'd be unusable in Ukraine, unless the goal was to get a lot of air crews killed.
One of the reasons they are being retired from the service as hopelessly 'obsolete'.
