this is an isekai with a clear medieval-like setting.
Some semblance of social contract has to exist, otherwise the universe's setting would implode. Even if you took a moment to think about it. If a guild routinely misattributes dungeon risk ratings, nobody would trust them. Look to how an "AAA" vs mere "AA" credit rating can make countries implode financially overnight.
And if that's too much / too close to home to ask -- as it is fiction -- at least in-universe consistent logic would be appreciated. I can read isekai fiction about a world where women above 20 are treated as "worthless goods", and an MC from "our world" who is like a kid in a candy store. But at least
that author recognized the need for some semblance of consistent back-story and worldbuilding.
And that's what turns a mind-numbing story, with inability to immerse at all, to at least junk-food status.
(I'm here for the dragon legs, honestly.)
If anything, I bet the guards would see all this as the trash taking itself out.
So that establishes guards as incompetent and untrustworthy. Why would people go to city centers at all? If civilians can be attacked in broad daylight by adventurers, and guards don't act to (at least minimally) protect populace?
Pretty art doesn't excuse terrible worldbuilding. That's the number one fault I've seen in most manga WN adaptations with immature authors. (And I read the WN/LNs. Typically the readers/commenters
are the editors.)