(Average+) The Rising of the Shield Hero

Series in one sentence:
Goofy from Kingdom Hearts is a loser.

Series in more sentences:
A lazy college student is suddenly warped to an RPG-like world, together with three strangers, each from an alternate version of Earth. They're told to be heroes a prophecy says will save their world from upcoming doom, and are informed they can't go home as long the attacks are going on.

The other three summons are gifted real weapons to work with, while Naofumi carries a shield and can only be a support character, making it hard for him to level up without help.
As the shield hero, he receives no respect from his surroundings, and when his short-lived teammate accuses him of molesting her, things go downhill even more and he's forced to purchase a sickly slave to fight his battles for him and give him that wanted chance of getting back home.

A simple adventure that's easy to follow, but it's weird to see the main character start off optimistic and youthful, but the rest of the anime be dark and brooding, even after things have improved and he's surrounded by people who worship the ground he shits on.
Let's say he aged 20 years after that false accusation and never recovered, I don't know.

The entire "devil shield" plot was wasted screentime as well. Every time Naofumi called upon these dark powers, the same drama happened, as if nobody learned from last time. It decreased the seriousness of it for me.  
It goes like this: Naofumi allows himself to get swayed by the evil voice that accompanies this power and becomes evil himself, even though he's only ever targeted his rage at the beasts he was already fighting. Still, everyone around him acts like he has become a problem and shout out at him. After only a few seconds of this, he's reminded his life isn't shit at all and comes back to reality. The end.

Why were his teammates so on edge every time? Just don't touch him and let the guy take care of the fight, seriously. I couldn't muster a shred of care for any of these scenes.

What else is there to mention.. perhaps I would've liked the bird to have stayed a non-speaking bird that isn't after Naofumi's dick, and more explanation as to why the shield hero is so hated, since the latter wasn't really explored.

Season 2, I guess?

-------------------------------------------------------------------------
5-5-2022 UPDATE:
Holy damn, season 2, I can't watch this anymore, stopped at episode 5.

It immediately throws you into a boring, basic adventure, wherein none of the characters say or do anything to make you want to stick around. It relies on the audience caring about this randomly inserted turtle minion with an existential crisis, as for the even less interesting green-haired girl, it was laughable.

Lowering my original score, I'm not watching the rest. It had 5 whole episodes to reel me in, that's about 2 hours, but offered me nothing. A possible/probable season 3 I won't visit.