Exactly my thought, altho TBF I think the situation had some complexities to it. For example, as prisoners slated to eventually be exterminated themselves, the kapos lived in fear just like the others, and it’s not surprising to me that some would be abusive where they could. (“shit rolls downhill” and all that)

Also, the better and more ruthless you were as a kapo, likely the better the Nazi guards liked you and gave you special perks, like your own room, better food, and a longer stay of death.

I’d strongly recommend reading Maus if you can. It’s the greatest graphic novel of all time IMO.