I very much doubt those numbers. The Ukrainians are claiming that they lost hundreds while inexplicably claiming to have inflicted those casualties on a qualitatively superior force?
Have you seen the footages and videos of Russian soldiers and their military vehicles stranded on roads throughout Ukraine? They are begging for fuel and food from locals.
Its an embarassment for a supposed super power, the poor logistics.
It is very difficult to fight a morally motivated population that fights to protect their homes and families, their bare existence. Even if you are superior in terms of firepower.
The Ukrainians wisely let them in instead of frontally attacking them. They let them into the cities and then they blast russian military vehicles that are sitting ducks on city streets. If the Ukrainians had done the opposite, that is if they had concentrated their forces and attacked the ruskis directly, this would have been over yesterday.
Putin is getting nervous. The russians havent accomplished anything, they havent taken any larger cities.