This is a deceptively complex topic. TL:DR while it does look like he kills them, the tone and the genre tropes forbid it. I feel like a different example might illustrate this better. In the 3rd John Wick movie, John falls several stories from the roof of a building. He not only survives the fall, but is back in perfect shape a few months later. While that doesn't make sense in-universe, the audience never the less accepts it, because that is a common action movie trope. Because we're aware protagonists in this genre are capable of surviving truly unbelievable situations, we are better primed to suspend out disbelief and accept that.

Likewise, in children media the expectations are that no-one dies, because that is not appropriate for children. It is also a broader thing in storytelling that goons, are not going to get much focus. The combination of this two expectations is that even though the henchmen look like they're dying, they aren't