I think from Russian eyes, it's hard to use the full warfighting capability index because it's against their own people. Eastern Ukraine is like 79% ethnically Russian. Hard to bomb cities with your own people in it, then after you've taken it, say "*yeah sorry we killed your family, but we're totally on your side, you know. We're Russian, together*". Russia wanted more ethnically Russian people in Ukraine to join them and help overthrow Zelenskyy, but that didn't happen.