@Lemongrassv Heheh. Cmiiw but as far as I know, many villagers (especially the poorer ones) don't get that kind of high education, so they basically eat whatever news they're told. The exact reason why they used to believe in witches :/
Also, there's this way of thinking, probably (It's usually the typical mindset in fiction)
Living sword -> Strong but cursed sword -> Possesses the user -> Evil -> Bloodthirsty
As for why the emperors get showered with praises despite this:
Emperors are thought very highly -> Sacrificed themselves to bring prosperity to the kingdom
Just a guess of what them people might think tho