Just because an anime character does incredible things doesn't mean that the people around them are going to acknowledge them properly. Actually, there are plenty of anime characters who deserve more respect but get very little of it from the other characters.
Perhaps the most noteworthy example of this trend is Saitama from One Punch Man, whose ability to defeat any and all enemies with a single punch is often completely ignored by his fellow heroes. There's also Tony Tony Chopper from One Piece, who is written off as a mere pet when he's actually a full member of the Straw Hat crew. There are also examples of this trope in nonfantasy settings - does anyone really think Fuutarou Uesugi from The Quintessential Quintuplets deserves all that scorn from the Nakano sisters when he's just trying to his job?
Let's show these downtrodden characters the love they aren't recieving in canon by voting up the best ones.
The titular character from Goblin Slayer has a singular priority, and if you're not sure what it is, refer to his name. He's often looked down upon by high-level adventurers because he only concerns himself with goblins. Despite the dangers that these creatures pose to the general population, destroying them just doesn't garner the same level of respect that taking out more powerful demons might. Luckily for Goblin Slayer, some people do appreciate his hard work - particularly those that the goblins have actually attacked.
Naofumi Iwatani is perhaps one of the most beleaguered heroes in the world of modern anime. He was summoned to the magical realm of Melromarc in order to become the Shield Hero, then immediately accused of crimes he didn't commit as a thin excuse for a political power grab. While the other heroes are treated like royalty no matter how many mistakes they make, Naofumi is out there actually helping people while recieving little credit for doing so.
By the end of the first season, his reputation had dramatically improved, but his poor treatment serves as one of the main conflicts for the majority of the series.
Yato was once a powerful god of destruction. Nowadays, he's trying to put his violent past behind him, and works as a 'delivery god' who does odd jobs for anyone willing to put five yen toward his goal of eventually buying a shrine for his worshippers he hopes to amass.
Those who don't know about Yato's past often consider him to be a pathetic deadbeat despite the fact that he spends the majority of his of his time engaged in supernatural battles to protect humanity, or doing time-consuming favors for pennies. Those who do know of his past don't seem to fully understand it, and heap blame on him that he doesn't deserve. Meanwhile, the guy is just trying to do good in the world.
When many anime fans think about characters who don't get the credit they deserve, Saitama is among the first to come to mind. After his life as a salaryman proves to be unfeasible, he undertakes a strict exercise program that grants him super strength. He becomes a hero 'for fun' and while he doesn't need to be lauded as the worlds' greatest hero, he'd still like a little bit more respect - and payment - than he recieves. Which is fair enough, because most people write off his accomplishments as impossible, claim credit for themselves, or falsely accuse him of villainy.
Actually, that's why he joins the Hero Association to begin with - he's hoping that he'll actually be able to build a good reputation for himself if he goes legit.