@Dao_Quan
At a guess, I think the Daxia elders aren't ignoring things, at least, but from some of the things that were said, it looks like the Problematic Dynasties in Daxia are corrupted, but USED to be way different than the scumbags they've turned into.
For example, it's mentioned that the First Generation Yihou Planet Lord founded the Gear Restriction Bureau and sacrificed himself to stop a Heaven-Tier Angel who went berserk and started devouring people.
The current Eighth Generation Planet Lord is (well, was) the scumbag who casually assassinates Daxia Fleet's admirals, is a slave trader, abuses his family's control of the Gear Restriction Bureau to bully or kill smaller fleet admirals before they can get too powerful and influential, etc etc.
I'd imagine, given that the backstory of the setting was a massive war between the human fleets and the much more advanced alien races (started, granted, because a Beiyang fleet commander was drunk-as-hell and went 'Man, fuck yer alien superior being shit, we can take ya. *urp* Fire da' cannons and get me another beer!'), that part of the reason that the Dragon Slayer Alliance keeps smelling like roses to the public while being absolutely shitty people and mass-murderers is that they have massively high reputations from the huge contributions their families made in the past.
...That, and they probably literally own the interstellar communications, which means that when news gets out, they can suppress little inconvenient little things like 'one of our members, the one we nominated for a peace prize, turned into a giant evil bug and tried to eat the planet' and other problems like that.
Still is a little weird that people just kinda go 'meh, whatever' at the whole 'casual mass-murder' thing, yeah.