You are right, you can’t use only information Ukraine or Russia provides. But it probably is the case that Ukraine was stomping Russia for pennies on the dollar earlier in the war. However, Russia is not a static force. They learn and change their tactics, and Russia spends more resources now than they did earlier.
It would be a grave mistake to stop aid to Ukraine while they are still willing and able to fight.
A ton of people using github barely understand the different between github and git and often think they are the same thing or that github and git are somewhat related more than they really are.