Some like to blame Zelensky for the war, but refuse to realize that 70% of Ukraine wants to be independent and decide their own future via democratic institutions. I don't support Zelensky as I think he is showing signs of a potential dictator down the road, but to say it is simply one person to blame for Russia's invasion is elementary thinking. Ukraine was peaceful all the while Moscow controlled it via puppet governments, and when the Ukrainian people set themselves free Russia annexed Crimea, instigated a war in the Donbas, used said instigation as a casus belli for the current invasion. I guess for some fighting back is equal to being attacked and supressed.
A good example and comparison - Ukraine was under indirect Russian control since 1991-2014, Poland decided to pursue an EU path. Ukraine was more developed and wealthy than Poland in 1991. Look at them today, Poland is light years ahead of Ukraine in every category, and they are independent and sovereign. Ukraine never was (1991-2014).
There is no way to justify Russia's war on Ukraine, and to claim that Russians are fighting for their "existence" is funny, it is more like Putin and his inner circle are fighting for existence.
The equipment losses Russia has sustained and will sustain is huge for them, billions in losses and they have to spend money to replenish their storage. Eventually money will run out especially when the western sanctions start to be felt in the next few months and especially years. Not to mention the EU decoupling from Russian gas which is yet to be felt.