But not all these soldiers are war criminals, often the people dieing in this grinder are the least responsible for what their country or army is doing.

Perhaps, but still infinitely more responsible than any person who isn't actively participating in the Russian invasion, which all of these guys definitely were.

Very very few combatants ever choose war as a solution. History shows that it's a choice made by those that never do any actual fighting, nor share in any risks of that decision, either.

These so-called leaders are always the ones that have sent our children to die to/kill each other. Everything else is propaganda.

War serves only profit itself and is never a "solution" without someone secretly standing to gain from it.

But not all these soldiers are war criminals

They literally are war criminals. They're participating in an invasion for no cause other than boosting Putin's ego.

And I've seen the propaganda advertisments in Russia "Go to war, support your country" and "Go to war, gives good money, support your family" and such.

Invading another country without cause makes you literally a war criminal. It is really ... that simple. Russia is literally a terrorist state at that moment. They've killed hundreds of civilians, thousands of Ukrainian fighters as well. Putting mines all over the place. Crippling and injuring so many other fighters and civilians as well. Sent terrorist groups.

If you're participating in such war, you are a war criminal. You can kill yourself. you can abandon your unit. You can bribe your commanders. You can run away before all this even starts. But by the moment you're invading another country and you're killing innocent people who have done NOTHING to you, you're a war criminal. It is really ... that simple. Coz it's "either I save myself or I kill these innocent people". That's a war criminal mindset coz it makes it seem as if you're a good guy in your mind. When you're not.