Even aside from the awesome fact that Ukraine has now shown themselves capable of taking ground without exposing their soldiers to enemy fire: Imagine how demoralising it must be for russian troops to realise they are trying to fend off an attack in which there are no soldiers. They must feel the hopelessness of fighting the Terminator. The ground vehicles assaulting their trench are lightly armoured vehicles that can shrug off quite a bit of small arms fire, and which can advance with complete disregard for mines, artillery, and enemy fire. If they take one out, Ukrainian engineers will just put one more together, and the operator can keep pushing while sitting safely out of sight.