Ukrainian forces were being trained and armed by NATO members for 8 years after euromaidan. It is ridiculous to believe that western powers were not trying to encircle Russia.

Even if the war was not worth the cost in lives, it is absurd to believe that Russia attacked Ukraine for shits and giggles. Or even for resources (Russia has some of the world's largest natural resource reserves), or land (largest country in the world), or people (Ukraine had a worse demographic problem than Russia, and the war has made things worse). The only thing they can plausibly gain is access to warm water ports (they already got that with crimea in 2014), and security against NATO.