The winner is always the one who simultaneously estimates their opponents most accurately, while their opponents estimate them least accurately.
It’s both Tsun tsu and the fundamental theory of poker, and as an outsider looking in, Ukraine is winning by this definition. They’ve made a good estimate and response to Russian capabilities while Russia both misestimated and misapplied it’s survey of forces. In this sense they are losing
However, what Russia has that Ukraine doesn’t, which it is using to great effect, is a deep, heavily invested in, propaganda and foreign influence campaign. Almost all negative impacts on global policy over the past 15 years tie back to this (Trump 2016, Brexit, Catalonia, The first invasion of Ukraine, Turkey and many more). It’s not something Ukraine can really compete against. It’s something the people of the world can compete against to support Ukraine however.