The art would be find if there was a reasonable level of cartoon villainy but the way the world outside of maybe 3 people and incidents has treated MC is enough to justify him being the edgelord that you get in a bunch of other stories.
The most reasonable behaviour from MC so far is not wanting to make a statue of himself
The doormat Mc is always a major negative to a series.
But in this series we have a lot of normal characters that are "not stupid" The king, the other high rank spirits that didn't know about the situation.
But how, you have poles where you strap spirits to the outside of carriages and hang them there, you have all these things the hero did, and claimed the MC did, the spirits would never believe those lies. With how blatant everyone who is evil is, how was it news to the spirits, how was it news to the king? They act deranged right in front of them, blatantly showing off they are evil. How do you expect me to believe the characters are not complicit and are actually intelligent when they can't notice what being done in front of them?
MC with social anxiety that leave him having trouble speaking up for himself, thats believable. People taking advantage of it, yes believable. But to take it so far, and for no one to be able to see through it, that makes no sense.
Like lets look at how his name was taken off of his inventions and the other name put on. Spirits were used to do this, spirits were ok with taking his name off. And further he couldn't remove the brand done by spirits at someone else request without seeking out specific ones, but they were able to undo his easily? So the spirits put more work into putting someone else name on the inventions?
Its just so inconsistent, if your going to be over the top, stay over the top. But having characters on the MC's side, yet for no reason that only started now makes no sense.