He’s a callous shitbag is why. That’s the correct answer. It has nothing to do with some deep thought on how the US exploits people, etc. It’s a response he gave because he doesn’t respect people regardless of whether they are dead or alive. The only people he respects are those in power.
I have read and watched every piece of SW media I could get my hands on for the last 30 years. There were absolutely some trash books or plotlines but nothing is worse than the 3 sequels and the Book of Boba Fett. Also, Solo got a bad rap.