These poor souls are being manipulated by propaganda and/or being forced to do this though. They aren't responsible for their own actions. We should feel sorry for them.
It's absolutely disgusting and the people committing these atrocities are obviously beyond repair and deserve everything that's coming for them. Still, there are also reports about Russian soldiers don't even knowing where they were heading or that they were going to fight a war, wondering why they are attacking their relatives in Ukraine and so forth. Nobody is defending what's been described in that tweet, nobody at all. You have to be a psychopath to do such stuff.
Our point is rather, every human being is a blank canvas when he's born. Maybe not completely blank as everybody has his character tendencies but the largest part of who we are is down to our upbringing and external influences. Everyone of us could be one of them if we were unlucky enough to be bornj in their stead. There's actually not even any room to argue otherwise unless you want to suggest that committing atrocities is ingrained in their genetics - and I'm sure you don't want to do that.
And that's important to understand because first, it is an enabler to see the roots of the conflict and take measures to prevent that something like this happens again and even more importantly in the short term, it helps us understand the enemy and his weaknesses and which triggers you can pull to demoralize his army and to foresee how he will behave in the future.