entire russian units took part in the invasion
Still it wasn't considered outright war between Ukraine and Russia at the time, more like skirmishes. Everybody knows that Russia meddled heavily.You can compare it to the border dispute between India and China, where there also is fighting, although it is only with primitive weapons like canes, there are casualties.China and India is not considered to be at war, but they very definitely have a very serious border dispute over a piece of land the British gave to China when India was a British colony.

















This is what is referred to when saying we are entering the 5th year.Yes there were problems before that, that could also be labelled war, but there's a huge difference between before the 24.02.2022 and after. With a thousand casualties every day for 4 years.
I'm not saying you are wrong, but you are kind of changing the subject.Donbas was not an existential problem for Ukraine, the full scale invasion is.